Oncor Electric Delivery 10-Q 4 May 20 2020 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2020	May 04, 2020	Dec. 31, 2019
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2020
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	333-100240
Entity Registrant Name	ONCOR ELECTRIC DELIVERY CO LLC
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	75-2967830
Entity Address, Address Line One	1616 Woodall Rodgers Fwy.
Entity Address, City or Town	Dallas
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	75202
City Area Code	214
Local Phone Number	486-2000
Title of 12(b) Security	None
No Trading Symbol Flag	true
Entity Current Reporting Status	No
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Capital account, interests outstanding	635,000,000	635,000,000	635,000,000
Entity Common Stock, Shares Outstanding		0
Entity Central Index Key	0001193311
Amendment Flag	false
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q1
Oncor Electric Delivery Holdings Company LLC [Member]
Entity Outstanding Membership Interests		80.25%
Texas Transmission and Investment LLC [Member]
Entity Outstanding Membership Interests		19.75%

Condensed Statements Of Consoli

Condensed Statements Of Consolidated Income - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Condensed Statements Of Consolidated Income [Abstract]
Operating revenues (Note 3)	$ 1,072	$ 1,016
Operating expenses:
Wholesale transmission service	245	260
Operation and maintenance	232	221
Depreciation and amortization	193	172
Provision in lieu of income taxes (Note 9)	29	25
Taxes other than amounts related to income taxes	131	122
Total operating expenses	830	800
Operating income	242	216
Other deductions and (income) - net (Note 10)	13	17
Nonoperating benefit in lieu of income taxes	(3)	(3)
Interest expense and related charges (Note 10)	101	86
Net income	$ 131	$ 116

Condensed Statements Of Conso_2

Condensed Statements Of Consolidated Comprehensive Income - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Condensed Statements Of Consolidated Comprehensive Income [Abstract]
Net income	$ 131	$ 116
Other comprehensive income (loss):
Net effects of cash flow hedges (net of tax) (Note 1)	(23)	(4)
Defined benefit pension plans (net of tax)	1	1
Total other comprehensive income (loss)	(22)	(3)
Comprehensive income	$ 109	$ 113

Condensed Statements Of Conso_3

Condensed Statements Of Consolidated Cash Flows - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Cash flows - operating activities:
Net income	$ 131	$ 116
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation and amortization, including regulatory amortization	213	192
Provision in lieu of deferred income taxes - net	13	8
Other - net		(2)
Changes in operating assets and liabilities:
Regulatory accounts related to reconcilable tariffs (Note 2)	(3)	(20)
Other operating assets and liabilities	(152)	(108)
Cash provided by operating activities	202	186
Cash flows - financing activities:
Issuances of long-term debt (Note 5)	1,250
Repayment of long-term debt (Note 5)	(462)
Net change in short-term borrowings (Note 4)	(46)	328
Capital contributions from members (Note 7)	87	70
Distributions to members (Note 7)	(91)	(71)
Debt discount and financing costs – net	(34)
Cash provided by financing activities	704	327
Cash flows - investing activities:
Capital expenditures	(628)	(523)
Other - net	8	12
Cash used in investing activities	(620)	(511)
Net change in cash and cash equivalents	286	2
Cash and cash equivalents - beginning balance	4	3
Cash and cash equivalents - ending balance	$ 290	$ 5

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 290	$ 4
Trade accounts receivable - net (Note 10)	656	661
Amounts receivable from members related to income taxes (Note 9)		3
Materials and supplies inventories - at average cost	159	148
Prepayments and other current assets	106	96
Total current assets	1,211	912
Investments and other property (Note 10)	126	133
Property, plant and equipment - net (Note 10)	19,816	19,370
Goodwill (Notes 1 and 11)	4,740	4,740
Regulatory assets (Note 2)	1,720	1,775
Operating lease ROU and other assets (Note 6)	141	106
Total assets	27,754	27,036
Current liabilities:
Short-term borrowings (Note 4)		46
Long-term debt due currently (Note 5)	148	608
Trade accounts payable	393	394
Amounts payable to members related to income taxes (Note 9)	32	22
Accrued taxes other than amounts related to income taxes	92	236
Accrued interest	94	83
Operating lease and other current liabilities (Note 6)	205	237
Total current liabilities	964	1,626
Long-term debt, less amounts due currently (Note 5)	9,256	8,017
Liability in lieu of deferred income taxes (Note 9)	1,846	1,821
Regulatory liabilities (Note 2)	2,786	2,793
Employee benefit, operating lease and other obligations (Notes 6, 8 and 10)	1,998	1,980
Total liabilities	16,850	16,237
Commitments and contingencies (Note 6)
Membership interests (Note 7):
Capital account ― number of interests outstanding 2020 and 2019 – 635,000,000	11,065	10,938
Accumulated other comprehensive loss	(161)	(139)
Total membership interests	10,904	10,799
Total liabilities and membership interests	$ 27,754	$ 27,036

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - shares	May 04, 2020	Mar. 31, 2020	Dec. 31, 2019
Condensed Consolidated Balance Sheets [Abstract]
Capital account, interests outstanding	635,000,000	635,000,000	635,000,000

Business And Significant Accoun

Business And Significant Accounting Policies	3 Months Ended
	Mar. 31, 2020
Business And Significant Accounting Policies [Abstract]
BUSINESS AND SIGNIFICANT ACCOUNTING POLICIES	1. BUSINESS AND SIGNIFICANT ACCOUNTING POLICIES  Description of Business  References in this report to “we,” “our,” “us” and “the company” are to Oncor and/or its subsidiaries as apparent in the context. See “Glossary” for definition of terms and abbreviations.  We are a regulated electricity transmission and distribution company principally engaged in providing delivery services to REPs that sell power in the north-central, eastern, western and panhandle regions of Texas. We are a direct, majority-owned subsidiary of Oncor Holdings, which is indirectly and wholly owned by Sempra. Oncor Holdings owns 80.25% of our outstanding membership interests and Texas Transmission owns 19.75% of our outstanding membership interests. We are managed as an integrated business; consequently, there is only one reportable segment.  Our condensed consolidated financial statements for the three months ended March 31, 2020, include the results of our wholly owned indirect subsidiary, NTU, which is a regulated utility that provides electricity transmission delivery service in the north-central, western and panhandle regions of Texas. We acquired NTU as part of the InfraREIT Acquisition that closed on May 16, 2019.  Ring-Fencing Measures  Since 2007, various ring-fencing measures have been taken to enhance our credit quality and the separateness between the Oncor Ring-Fenced Entities and entities with ownership interests in Oncor or Oncor Holdings. These ring-fencing measures serve to mitigate the Oncor Ring-Fenced Entities’ credit exposure to owners of Oncor and Oncor Holdings, and to reduce the risk that the assets and liabilities of Oncor Ring-Fenced Entities would be substantively consolidated with the assets and liabilities of any direct or indirect owners of Oncor and Oncor Holdings in connection with a bankruptcy of any such entities. These measures include the November 2008 sale of 19.75% of Oncor’s equity interests to Texas Transmission.  In March 2018, Sempra indirectly acquired Oncor Holdings through the Sempra Acquisition. The Sempra Acquisition was consummated after obtaining the approval of the bankruptcy court in the EFH Bankruptcy Proceedings and the PUCT. The PUCT approval was obtained in Docket No. 47675, and the final order issued in that docket (Sempra Order) outlines certain ring-fencing measures, governance mechanisms and restrictions that apply after the Sempra Acquisition. As a result of these ring-fencing measures, Sempra does not control Oncor, and the ring-fencing measures limit Sempra’s ability to direct the management, policies and operations of Oncor, including the deployment or disposition of Oncor’s assets, declarations of dividends, strategic planning and other important corporate issues and actions.  None of the assets of the Oncor Ring-Fenced Entities are available to satisfy the debt or obligations of any Sempra entity or any other direct or indirect owner of Oncor or Oncor Holdings. The assets and liabilities of the Oncor Ring-Fenced Entities are separate and distinct from those of any Sempra entities and any other direct or indirect owner of Oncor or Oncor Holdings. We do not bear any liability for debt or contractual obligations of Sempra and its affiliates or any other direct or indirect owner of Oncor or Oncor Holdings, and vice versa. Accordingly, our operations are conducted, and our cash flows are managed, independently from Sempra and its affiliates and any other direct or indirect owner of Oncor or Oncor Holdings.  Oncor is a limited liability company governed by a board of directors, not its members. The Sempra Order and our Limited Liability Company Agreement require that the board of directors of Oncor consist of thirteen members, constituted as follows:  · seven Disinterested Directors, who (i) shall be independent directors in all material respects under the rules of the New York Stock Exchange in relation to Sempra or its subsidiaries and affiliated entities and any entity with a direct or indirect ownership interest in Oncor or Oncor Holdings, and (ii) shall have no material relationship with Sempra or its subsidiaries or affiliated entities or any entity with a direct or indirect ownership interest in Oncor or Oncor Holdings, currently or within the previous ten years; · two members designated by Sempra (through Oncor Holdings); · two members designated by Texas Transmission; and · two current or former officers of Oncor (the Oncor Officer Directors), currently Robert S. Shapard and E. Allen Nye, Jr., who are our Chairman of the Board and Chief Executive, respectively.  In order for a current or former officer of Oncor to be eligible to serve as an Oncor Officer Director, the officer cannot have worked for Sempra or any of its affiliates (excluding Oncor Holdings and Oncor) or any other entity with a direct or indirect ownership interest in Oncor or Oncor Holdings in the ten-year period prior to the officer being employed by Oncor. Oncor Holdings, at the direction of STIH, has the right to nominate and/or seek the removal of the Oncor Officer Directors, subject to approval by a majority of the Oncor board of directors. STIH is a wholly owned indirect subsidiary of, and controlled by, Sempra following the Sempra Acquisition.  In addition, the Sempra Order provides that Oncor’s board cannot be overruled by the board of Sempra or any of its subsidiaries on dividend policy, the issuance of dividends or other distributions (except for contractual tax payments), debt issuance, capital expenditures, operation and maintenance expenditures, management and service fees, and appointment or removal of board members, provided that certain actions may also require the additional approval of the Oncor Holdings board of directors. The Sempra Order also provides that any changes to the size, composition, structure or rights of the board must first be approved by the PUCT. In addition, if Sempra acquires Texas Transmission’s interest in Oncor, the two board positions on Oncor’s board of directors that Texas Transmission is entitled to appoint will be eliminated and the size of Oncor’s board of directors will be reduced by two.  Additional regulatory commitments, governance mechanisms and restrictions provided in the Sempra Order and our Limited Liability Company Agreement to ring-fence Oncor from its owners include, among others:  · A majority of the Disinterested Directors of Oncor must approve any annual or multi-year budget if the aggregate amount of capital expenditures or operating and maintenance expenditures in such budget is more than a 10% increase or decrease from the corresponding amounts of such expenditures in the budget for the preceding fiscal year or multi-year period, as applicable;  · Oncor may not pay any dividends or make any other distributions (except for contractual tax payments) if a majority of its Disinterested Directors determines that it is in the best interests of Oncor to retain such amounts to meet expected future requirements;  · At all times, Oncor will remain in compliance with the debt-to-equity ratio established by the PUCT from time to time for ratemaking purposes, and Oncor will not pay dividends or other distributions (except for contractual tax payments), if that payment would cause its debt-to-equity ratio to exceed the debt-to-equity ratio approved by the PUCT;  · If the credit rating on Oncor’s senior secured debt by any of the three major rating agencies falls below BBB (or the equivalent), Oncor will suspend dividends and other distributions (except for contractual tax payments), unless otherwise allowed by the PUCT;  · Without the prior approval of the PUCT, neither Sempra nor any of its affiliates (excluding Oncor) will incur, guaranty or pledge assets in respect of any indebtedness that is dependent on the revenues of Oncor in more than a proportionate degree than the other revenues of Sempra or on the stock of Oncor, and there will be no debt at STH or STIH at any time following the closing of the Sempra Acquisition;  · Neither Oncor nor Oncor Holdings will lend money to or borrow money from Sempra or any of its affiliates (other than Oncor subsidiaries), or any entity with a direct or indirect ownership interest in Oncor or Oncor Holdings, and neither Oncor nor Oncor Holdings will share credit facilities with Sempra or any of its affiliates (other than Oncor subsidiaries), or any entity with a direct or indirect ownership interest in Oncor or Oncor Holdings;  · There must be maintained certain “separateness measures” that reinforce the financial separation of Oncor from its owners, including a requirement that dealings between Oncor, Oncor Holdings and their subsidiaries with Sempra, any of Sempra’s other affiliates or any entity with a direct or indirect ownership interest in Oncor or Oncor Holdings, must be on an arm’s-length basis, limitations on affiliate transactions, separate recordkeeping requirements and a prohibition on Sempra or its affiliates pledging Oncor assets or stock for any entity other than Oncor; and  · Sempra will continue to hold indirectly at least 51% of the ownership interests in Oncor and Oncor Holdings for at least five years following the closing of the Sempra Acquisition, unless otherwise specifically authorized by the PUCT.  Basis of Presentation  These unaudited condensed consolidated financial statements should be read in conjunction with the audited financial statements and related notes included in our 2019 Form 10-K. In the opinion of Oncor management, all adjustments (consisting of normal recurring accruals) necessary for a fair presentation of the results of operations and financial position have been made. We have evaluated all subsequent events through the date the financial statements were issued. All appropriate intercompany items and transactions have been eliminated in consolidation. The results of operations for an interim period may not give a true indication of results for a full year due to seasonality (see Note 13 to Financial Statements in our 2019 Form 10-K for additional information regarding quarterly results of operations).  Our consolidated financial statements have been prepared in accordance with GAAP governing rate-regulated operations. All dollar amounts in the financial statements and tables in the notes are stated in millions of U.S. dollars unless otherwise indicated.  Use of Estimates  Preparation of our financial statements requires management to make estimates and assumptions about future events that affect the reporting of assets and liabilities at the balance sheet dates and the reported amounts of revenue and expense, including fair value measurements. In the event estimates and/or assumptions prove to be different from actual amounts, adjustments are made in subsequent periods to reflect more current information. No material adjustments were made to previous estimates or assumptions during the current period.  Interest Rate Derivatives and Hedge Accounting  We are exposed to interest rates primarily as a result of our current and expected use of financing. We may, from time to time, utilize interest rate derivative instruments typically designated as cash flow hedges, to lock in interest rates in anticipation of future financings. We may designate an interest rate derivative instrument as a cash flow hedge if it effectively converts anticipated cash flows associated with interest payments to a fixed dollar amount. In accounting for cash flow hedges, derivative assets and liabilities are recorded on the balance sheet at fair value with an offset to other comprehensive income. Amounts remain in accumulated other comprehensive income and are reclassified into net income as the interest expense on the related debt affects net income. See Note 5 for details on our interest rate hedging activity.  Impairment of Long-Lived Assets and Goodwill  We evaluate long-lived assets (including intangible assets with finite lives) for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable.  We also evaluate goodwill for impairment annually on October 1 and whenever events or changes in circumstances indicate that an impairment may exist. The determination of the existence of these and other indications of impairment involves judgments that are subjective in nature and may require the use of estimates in forecasting future results and cash flows.  Changes in Accounting Standards  Topic 326, “Financial Instruments—Credit Losses” – In June 2016 the FASB issued ASU No. 2016-13, which changes how entities account for credit losses on receivables and certain other financial assets. The guidance requires use of a current expected credit loss model, which may result in earlier recognition of credit losses than under previous accounting standards. We adopted the new standard effective January 1, 2020. The adoption of the new standard did not have a material impact on our consolidated financial statements.  Topic 848, “Facilitation of the Effects of Reference Rate Reform on Financial Reporting” – In March 2020 the FASB issued ASU No. 2020-04, which provides optional expedients and exceptions for applying GAAP to contracts, hedging relationships, and other transactions that reference LIBOR or another reference rate expected to be discontinued because of reference rate reform. ASU No. 2020-04 is effective for all entities as of March 12, 2020 through December 31, 2022. The standard allows entities to account for contract modifications as an event that does not require reassessment or remeasurement (i.e., as a continuation of the existing contract). We are currently evaluating the optional expedients and exceptions under the standard. 

Regulatory Matters

Regulatory Matters	3 Months Ended
	Mar. 31, 2020
Regulatory Matters [Abstract]
REGULATORY MATTERS	2. REGULATORY MATTERS  Regulatory Assets and Liabilities  Recognition of regulatory assets and liabilities and the periods over which they are to be recovered or refunded through rate regulation reflect the decisions of the PUCT. Components of our regulatory assets and liabilities and their remaining recovery periods as of March 31, 2020 are provided in the table below. Amounts not currently earning a return through rate regulation are noted.     Remaining Rate Recovery/ Amortization Period  At March 31, 2020 At March 31, 2020 At December 31, 2019  Regulatory assets:  Employee retirement liability (a)(b)(c) To be determined $ 615 $ 623  Employee retirement costs being amortized 8 years 253 262  Employee retirement costs incurred since the last rate review period (b) To be determined 76 79  Self-insurance reserve (primarily storm recovery costs) being amortized 8 years 298 309  Self-insurance reserve incurred since the last rate review period (primarily storm related) (b) To be determined 221 238  Securities reacquisition costs Lives of related debt 27 29  Deferred conventional meter and metering facilities depreciation 1 year 10 15  Under-recovered AMS costs 8 years 165 170  Energy efficiency performance bonus (a) 1 year or less 7 9  Wholesale distribution substation service To be determined 39 34  Other regulatory assets (d) Various 9 7  Total regulatory assets 1,720 1,775   Regulatory liabilities:  Estimated net removal costs Lives of related assets 1,199 1,178  Excess deferred taxes Primarily over lives of related assets 1,557 1,574  Over-recovered wholesale transmission service expense (a) 1 year or less 14 30  Other regulatory liabilities Various 16 11  Total regulatory liabilities 2,786 2,793  Net regulatory assets (liabilities) $ (1,066) $ (1,018) ____________ (a) Not earning a return in the regulatory rate-setting process. (b) Recovery is specifically authorized by statute or by the PUCT, subject to reasonableness review. (c) Represents unfunded liabilities recorded in accordance with pension and OPEB accounting standards. (d) Includes $1 million in regulatory assets established to track our incremental costs related to the impact of COVID-19, including costs relating to our pandemic response plan. PUCT Project No. 50664 Issues Related to the State of Disaster for the Coronavirus Disease 2019  On March 26, 2020, the PUCT issued an order in PUCT Project No. 50664 Issues Related to the State of Disaster for the Coronavirus Disease 2019 creating the COVID-19 Electricity Relief Program (COVID-19 ERP) to aid certain eligible residential customers unable to pay their electricity bills as a result of COVID-19 impacts. To fund that program, the PUCT order also provided for an initial $0.33 per MWh surcharge to be collected by transmission and distribution utilities through rates and directed ERCOT to provide an aggregate amount of $15 million in loans to those transmission and distribution utilities for the initial funding of the COVID-19 ERP. As a result, we filed a tariff rider on April 1, 2020 implementing the surcharge. The PUCT order provides that we may request an increase of the surcharge amount if the collections appear insufficient to cover eligible costs of the COVID-19 ERP. Surcharge collections will be recorded as a regulatory liability until the funds are used. Surcharge collections may only be used to reimburse transmission and distribution utilities and REPs for eligible unpaid bills from residential customers enrolled in the COVID-19 ERP, to cover costs of a third-party administrator to administer the eligibility process, and to reimburse ERCOT for the initial funding of the program. Pursuant to an order issued April 17, 2020, the COVID-19 ERP will expire July 17, 2020 unless extended by the PUCT.  Pursuant to the PUCT order, we received an unsecured loan from ERCOT on April 9, 2020 in the amount of $7 million. Under the terms of the loan agreement, we must repay the amount of the loan prior to September 26, 2020, (the original expiration date of the COVID-19 ERP pursuant to the March 26, 2020 PUCT order) or such repayment date as may be set forth in a PUCT order.  The PUCT also authorized the transmission and distribution utilities to use a regulatory asset accounting mechanism and a subsequent process to seek future recovery of expenses resulting from the effects of COVID-19. Therefore, we are recording incremental costs incurred by Oncor resulting from the effects of COVID-19, including costs relating to the implementation of our pandemic response plan, as a regulatory asset.

Revenues

Revenues	3 Months Ended
	Mar. 31, 2020
Revenues [Abstract]
REVENUES	3. REVENUES  General  Our revenue is billed monthly under tariffs approved by the PUCT and the majority of revenues are related to providing electric delivery service to consumers. Tariff rates are designed to recover the cost of providing electric delivery service to customers including a reasonable rate of return on invested capital. As the volumes delivered can be directly measured, our revenues are recognized when the underlying service has been provided in an amount prescribed by the related tariff. We recognize revenue in the amount that we have the right to invoice. Substantially all of our revenues are from contracts with customers except for alternative revenue program revenues discussed below.  Reconcilable Tariffs  The PUCT has designated certain tariffs (primarily TCRF and EECRF) as reconcilable, which means the differences between amounts billed under these tariffs and the related incurred costs are deferred as either regulatory assets or regulatory liabilities. Accordingly, at prescribed intervals, future tariffs are adjusted to either repay regulatory liabilities or collect regulatory assets.  Alternative Revenue Program  The PUCT has implemented an incentive program allowing us to earn performance bonuses by exceeding PUCT-approved energy efficiency program targets. This incentive program and the related performance bonus revenues are considered an “alternative revenue program” under GAAP. Annual performance bonuses are recognized as revenue when approved by the PUCT, typically in the third or fourth quarter each year.  Disaggregation of Revenues  The following table reflects electric delivery revenues disaggregated by tariff for the three months ended March 31, 2020 and 2019:   Three Months Ended March 31,  2020 2019  Operating revenues  Revenues contributing to earnings:  Distribution base revenues $ 496 $ 499  Transmission base revenues (TCOS revenues):  Billed to third-party wholesale customers 196 143  Billed to REPs serving Oncor distribution customers, through TCRF 109 85  Total transmission base revenues 305 228  Other miscellaneous revenues 16 17  Total revenues contributing to earnings 817 744   Revenues collected for pass-through expenses:  TCRF - third-party wholesale transmission service 245 260  EECRF and other regulatory charges 10 12  Revenues collected for pass-through expenses 255 272   Total operating revenues $ 1,072 $ 1,016  Customers  Our distribution customers consist of approximately 90 REPs and certain electric cooperatives in our certificated service area. The consumers of the electricity we deliver are free to choose their electricity supplier from REPs who compete for their business. Our transmission base revenues are collected from load serving entities benefiting from our transmission system. Our transmission customers consist of municipalities, electric cooperatives and other distribution companies. REP subsidiaries of our two largest counterparties represented 25% and 18% of our total operating revenues for the three months ended March 31, 2020. No other customer represented more than 10% of our total operating revenues.  Variability  Our revenues and cash flows are subject to seasonality, timing of customer billings, weather conditions and other electricity usage drivers, with revenues being highest in the summer. Payment is due 35 days after invoicing. Under a PUCT rule relating to the Certification of Retail Electric Providers, write-offs of uncollectible amounts owed by REPs are recoverable as a regulatory asset.  Pass-through Expenses  Expenses which are allowed to be passed-through to customers (primarily, third party wholesale transmission service and energy efficiency program costs) are generally recognized as revenue at the time the costs are incurred. Franchise taxes are assessed by local governmental bodies, based on kWh delivered and are not a “pass-through” item. The rates we charge customers are intended to recover the franchise taxes, but we are not acting as an agent to collect the taxes from customers; therefore, franchise taxes are reported as a principal component of “taxes other than amounts related to income taxes” instead of a reduction to “revenues” in the income statement.

Short-Term Borrowings

Short-Term Borrowings	3 Months Ended
	Mar. 31, 2020
Short-Term Borrowings [Abstract]
SHORT-TERM BORROWINGS	4. SHORT-TERM BORROWINGS  At March 31, 2020 and December 31, 2019, outstanding short-term borrowings under our CP Program and Credit Facility consisted of the following:   At March 31, At December 31,  2020 2019  Total credit facility borrowing capacity $ 2,000 $ 2,000  Commercial paper outstanding (a) - (46)  Credit facility outstanding (b) - -  Letters of credit outstanding (c) (9) (10)  Available unused credit $ 1,991 $ 1,944 ____________ a) The weighted average interest rate for commercial paper was 1.84% at December 31, 2019. b) At March 31, 2020, the applicable interest rate for any outstanding borrowings was LIBOR plus 1.00%. c) The interest rate on outstanding letters of credit at both March 31, 2020 and December 31, 2019 was 1.20% based on our credit ratings. CP Program  In March 2018, we established the CP Program, under which we may issue CP Notes on a private placement basis up to a maximum aggregate face or principal amount outstanding at any time of $2.0 billion. The proceeds of CP Notes issued under the CP Program are used for working capital and general corporate purposes. The CP Program obtains liquidity support from our Credit Facility, which is discussed below. We may utilize either the CP Program or the Credit Facility, at our option, to meet our funding needs.  Credit Facility  In November 2017, we entered into a $2.0 billion unsecured Credit Facility to be used for working capital and general corporate purposes, issuances of letters of credit and support our CP Program . We may request increases in our borrowing capacity in increments of not less than $100 million, not to exceed $400 million in the aggregate provided certain conditions are met, including lender approvals. The Credit Facility’s five -year term expires in November 2022 and gives us the option of requesting up to two one -year extensions, with such extensions subject to certain conditions and lender approvals.  Ma rch 2020 Term Loan Agreement  On March 23, 2020, we entered into a short-term unsecured term loan credit agreement (March 2020 Term Loan Agreement) in an aggregate principal amount of $350 million, which may be increased, at our option and upon the agreement of one or more existing or additional lenders, by an aggregate principal amount of between $50 million and $100 million prior to our first borrowing under the March 2020 Term Loan Agreement. The March 2020 Term Loan Agreement has a maturity date of March 22, 2021 , which may be extended once, in whole or part, at our option and upon the payment to the extending lenders of an extension fee to be agreed upon by such extending lenders, to a date not later than September 24, 2021 . We may borrow up to $350 million in up to four borrowings which may be made, at our option, at any time between April 1, 2020 and July 21, 2020. Upon the earlier to occur of the fourth borrowing and July 21, 2020, the unused commitments of the lenders to make term loans shall terminate. Loans under the March 2020 Term Loan Agreement bear interest at per annum rates equal to, at our option, (i) LIBOR plus 0.675% , or (ii) an alternate base rate (the highest of (1) the prime rate of Wells Fargo Bank, National Association, the administrative agent and a lender under the agreement, (2) the federal funds effective rate plus 0.50% , and (3) daily one-month LIBOR plus 1% ). No amounts were outstanding under the March 2020 Term Loan Agreement as of March 31, 2020. 

Long-Term Debt

Long-Term Debt	3 Months Ended
	Mar. 31, 2020
Long-Term Debt [Abstract]
LONG-TERM DEBT	5. LONG-TERM DEBT  Our senior notes are secured by a first priority lien on certain transmission and distribution assets equally and ratably with all of Oncor’s other secured indebtedness. See “Deed of Trust” below for additional information. At March 31, 2020 and December 31, 2019, our long-term debt consisted of the following:   March 31, December 31,  2020 2019  Fixed Rate Secured:  5.75% Senior Notes due September 30, 2020 $ 126 $ 126  8.50% Senior Notes, Series C, due December 30, 2020 13 14  4.10% Senior Notes, due June 1, 2022 400 400  7.00% Debentures due September 1, 2022 482 482  2.75% Senior Notes due June 1, 2024 500 500  2.95% Senior Notes due April 1, 2025 350 350  3.86% Senior Notes, Series A, due December 3, 2025 174 174  3.86% Senior Notes, Series B, due January 14, 2026 38 38  3.70% Senior Notes due November 15, 2028 650 650  5.75% Senior Notes due March 15, 2029 318 318  7.25% Senior Notes, Series B, due December 30, 2029 36 36  2.75% Senior Notes due May 15, 2030 400 -  6.47% Senior Notes, Series A, due September 30, 2030 82 83  7.00% Senior Notes due May 1, 2032 500 500  7.25% Senior Notes due January 15, 2033 350 350  7.50% Senior Notes due September 1, 2038 300 300  5.25% Senior Notes due September 30, 2040 475 475  4.55% Senior Notes due December 1, 2041 400 400  5.30% Senior Notes due June 1, 2042 500 500  3.75% Senior Notes due April 1, 2045 550 550  3.80% Senior Notes due September 30, 2047 325 325  4.10% Senior Notes due November 15, 2048 450 450  3.80% Senior Notes, due June 1, 2049 500 500  3.10% Senior Notes, due September 15, 2049 700 700  3.70% Senior Notes due May 15, 2050 400 -  Secured long-term debt 9,019 8,221  Unsecured:  Term loan credit agreement maturing October 6, 2020 - 460  Term loan credit agreement maturing June 1, 2021 450 -  Total long-term debt 9,469 8,681  Unamortized discount and debt issuance costs (65) (56)  Less amount due currently (148) (608)  Long-term debt, less amounts due currently $ 9,256 $ 8,017 Long-Term Debt-Related Activity in 2020  Debt Issuances  On March 20, 2020, we completed a sale of $400 million aggregate principal amount of 2.75% Senior Secured Notes due 2030 (2030 Notes) and $400 million aggregate principal amount of 3.70% Senior Secured Notes due 2050 (2050 Notes and, together with the 2030 Notes, the Notes). We used the proceeds (net of the initial purchasers’ discount, fees and expenses) of approximately $790 million from the sale of the Notes for general corporate purposes, including the repayment of short-term and long-term debt.  The Notes were issued pursuant to the provisions of an Indenture, dated as of August 1, 2002, between Oncor and The Bank of New York Mellon Trust Company, N.A. (as successor to The Bank of New York Mellon, formerly The Bank of New York) (as amended and supplemented, the Indenture). The 2030 Notes and the 2050 Notes each constitute a separate series of notes under the Indenture, but will be treated together with Oncor’s other outstanding debt securities issued under the Indenture for amendments and waivers and for taking certain other actions.  The Notes were issued in separate private placements and were not registered under the Securities Act. We have agreed, subject to certain exceptions, to register with the SEC notes having substantially identical terms as the Notes (except for provisions relating to the transfer restriction and payment of additional interest) as part of our offers to exchange freely tradable exchange notes for the Notes. We have agreed to use commercially reasonable efforts to cause the exchange offers to be completed within 315 days after the applicable issue date of the Notes. If a registration statement for the exchange offers is not declared effective by the SEC within 270 days after the applicable issue date of the Notes or the exchange offers are not completed within 315 days after the applicable issue date of the Notes (an exchange default), then the annual interest rate on each series of the Notes will increase 50 basis points per annum until the earlier of the expiration of the exchange default or the second anniversary of the issue dates of the Notes.  January 2020 Term Loan Credit Agreement  On January 28, 2020, we executed a $450 million term loan credit agreement that matures on June 1, 2021 (January 2020 Term Loan Agreement). The January 2020 Term Loan Agreement provides that we can borrow the full amount in up to four borrowings by April 27, 2020. We borrowed $163 million on January 29, 2020, $55 million on February 28, 2020 and $232 million on March 1 7 , 2020 under the January 2020 Term Loan Agreement. At March 31, 2020, borrowings under the January 2020 Term Loan Agreement totaled $450 million, the full amount available under the agreement.  The proceeds from each borrowing were used for general corporate purposes, including the repayment of notes outstanding under our CP Program. Loans under the January 2020 Term Loan Agreement bear interest at per annum rates equal to, at our option, (i) LIBOR plus 0.50% until June 1, 2021, or (ii) an alternate base rate (the highest of (1) the prime rate of Sumitomo Mitsui Banking Corporation, the administrative agent and a lender under the agreement, (2) the federal funds effective rate plus 0.50% , and (3) daily one-month LIBOR plus 1% ).  Interest Rate Hedge Transactions  In February and March of 2020, we entered into interest rate hedge transactions hedging the variability of benchmark bond rates used to determine interest rates on anticipated issuances of ten -year and thirty -year senior secured notes. The hedges were terminated in March 2020 upon our issuance of the senior secured notes discussed in “Debt Issuances” above . We recognized a $29 million ( $23 million after-tax) loss related to the fair value of the hedge transactions in accumulated other comprehensive loss. We expect approximately $4 million of the amount reported in accumulated other comprehensive loss at March 31, 2020 related to interest rate hedges to be reclassified into net income as an increase to interest expense within the next 12 months, including $2 million from the current period transactions.  Debt Repayments  Repayments of long-term debt in the three months ended March 31, 2020 included $460 million principal amount borrowed under a term loan agreement entered into in 2019 that was to mature in October 2020 (2019 Term Loan Agreement) and $2 million principal amount of the quarterly amortizing debt for senior secured notes issued under one of our Note Purchase Agreements . The $460 million repaid under the 2019 Term Loan Agreement constituted all amounts outstanding under that agreement, and as a result of that repayment the agreement is no longer in effect.  Deed of Trust  Our secured indebtedness is secured equally and ratably by a first priority lien on property we acquired or constructed for the transmission and distribution of electricity. The property is mortgaged under the Deed of Trust. The Deed of Trust permits us to secure indebtedness with the lien of the Deed of Trust up to the aggregate of (i) the amount of available bond credits, and (ii) 85% of the lower of the fair value or cost of certain property additions that could be certified to the Deed of Trust collateral agent. At March 31, 2020, the amount of available bond credits was $1.973 billion and the amount of future debt we could secure with property additions, subject to those property additions being certified to the Deed of Trust collateral agent, was $2.602 billion.  Borrowings under the CP Program, the Credit Facility, and our term loan credit agreements are not secured.  Maturities  Long-term maturities (including current maturities) at March 31, 2020, are as follows:    Year Amount  2020 (excluding first three months of 2020) $ 148  2021 459  2022 891  2023 10  2024 510  Thereafter 7,451  Unamortized discount and debt issuance costs (65)  Total $ 9,404  Fair Value of Long-Term Debt  At March 31, 2020 and December 31, 2019, the estimated fair value of our long-term debt (including current maturities) totaled $10.734 billion and $10.003 billion, respectively, and the carrying amount totaled $9.404 billion and $8.625 billion, respectively. The fair value is estimated using observable market data, representing Level 2 valuations under accounting standards related to the determination of fair value.

Commitments And Contingencies

Commitments And Contingencies	3 Months Ended
	Mar. 31, 2020
Commitments And Contingencies [Abstract]
COMMITMENTS AND CONTINGENCIES	6. COMMITMENTS AND CONTINGENCIES  Legal/Regulatory Proceedings  We are involved in various legal and administrative proceedings in the normal course of business, the ultimate resolution of which, in the opinion of management, should not have a material effect upon our financial position, results of operations or cash flows. See Note 2 above and Note 8 to Financial Statements in our 2019 Form 10-K for additional information regarding our regulatory and legal proceedings, respectively.  Leases  As lessee, our leased assets primarily consist of our vehicle fleet and real estate leased for company offices and service centers. Our leases are accounted for as operating leases for both GAAP and rate-making purposes. We generally recognize operating lease costs on a straight-line basis over the lease term in operating expenses. We are not a lessor to any material lease contracts.  In December 2019, we entered into a 15 year lease agreement for replacement office space. The operating lease partially commenced in February 2020 and increased our lease obligation by $24 million.  The table below presents the maturity analysis of our lease liabilities and reconciliation to the present value of lease liabilities:    Year Amount  2020 (remaining nine months) $ 23  2021 28  2022 24  2023 18  2024 12  Thereafter 28  Total undiscounted lease payments 133  Less imputed interest (12)  Total future minimum lease payments $ 121   See Note 8 to Financial Statements in our 2019 Form 10-K for additional information on leases.

Membership Interests

Membership Interests	3 Months Ended
	Mar. 31, 2020
Membership Interests [Abstract]
MEMBERSHIP INTERESTS	 7. MEMBERSHIP INTERESTS  Cash Contributions   We received cash capital contributions from our members on February 18, 2020 and April 27, 2020 each totaling $87 million.  Cash Distributions   The PUCT order issued in the Sempra Acquisition and our Limited Liability Company Agreement set forth various restrictions on distributions to our members. Among those restrictions is the commitment that we will make no distributions that would cause us to be out of compliance with the PUCT’s approved debt-to-equity ratio, which is currently 57.5% debt to 42.5% equity. The distribution restrictions also include the ability of our board, a majority of the Disinterested Directors, or either of the two member directors designated by Texas Transmission to limit distributions to the extent each determines it is necessary to meet expected future requirements of Oncor (including continuing compliance with the PUCT debt-to-equity ratio commitment). At March 31, 2020, we had $301 million available to distribute to our members as our regulatory capitalization ratio was 56.5% debt to 43.5% equity.  The PUCT has the authority to determine what types of debt and equity are included in a utility’s debt-to-equity ratio. For purposes of this ratio, debt is calculated as long-term debt including any finance leases plus unamortized gains on reacquired debt less unamortized issuance expenses, premiums and losses on reacquired debt. Equity is calculated as membership interests determined in accordance with GAAP, excluding accumulated other comprehensive loss and the effects of acquisition accounting from a 2007 transaction.  On February 19, 2020, our board of directors declared a cash distribution of $91 million, which was paid to our members on February 20, 2020. On April 29, 2020, our board of directors declared a cash distribution of $91 million, which was paid to our members on April 30, 2020. Membership Interests  The following tables present the changes to membership interests during the three months ended March 31, 2020 and 2019, net of tax:    Capital Accounts Accumulated Other Comprehensive Income (Loss) Total Membership Interests  Three Months Ended March 31, 2020  Balance at December 31, 2019 $ 10,938 $ (139) $ 10,799  Net income 131 - 131  Distributions (91) - (91)  Capital contributions 87 - 87  Net effects of cash flow hedges (Note 5) - (23) (23)  Defined benefit pension plans - 1 1  Balance at March 31, 2020 $ 11,065 $ (161) $ 10,904     Capital Accounts Accumulated Other Comprehensive Income (Loss) Total Membership Interests  Three Months Ended March 31, 2019  Balance at December 31, 2018 $ 8,624 $ (164) $ 8,460  Net income 116 - 116  Distributions (71) - (71)  Capital contributions 70 - 70  Net effects of cash flow hedges 4 (4) -  Defined benefit pension plans - 1 1  Balance at March 31, 2019 $ 8,743 $ (167) $ 8,576  Accumulated Other Comprehensive Income (Loss) (AOCI)  The following table presents the changes to AOCI for the three months ended March 31, 2020 and 2019, net of tax:   Cash Flow Hedges – Interest Rate Swaps Defined Benefit Pension and OPEB Plans Accumulated Other Comprehensive Income (Loss)  Balance at December 31, 2019 $ (18) $ (121) $ (139)  Defined benefit pension plans - 1 1  Cash flow hedges — net decrease in fair value of derivatives (net of tax benefit of $6 ) (Note 5) (23) - (23)  Balance at March 31, 2020 $ (41) $ (120) $ (161)   Balance at December 31, 2018 $ (16) $ (148) $ (164)  Defined benefit pension plans - 1 1  Amounts reclassified from accumulated other comprehensive income (loss) to capital account (4) - (4)  Balance at March 31, 2019 $ (20) $ (147) $ (167) 

Pension And OPEB Plans

Pension And OPEB Plans	3 Months Ended
	Mar. 31, 2020
Pension And OPEB Plans [Abstract]
PENSION AND OPEB PLANS	8. PENSION AND OPEB PLANS  Pension Plans  We sponsor the Oncor Retirement Plan and also have liabilities under the Vistra Retirement Plan, both of which are qualified pension plans under Section 401(a) of the Internal Revenue Code of 1986, as amended, and are subject to the provisions of ERISA. Employees do not contribute to either plan. We also have a Supplemental Retirement Plan for certain employees whose retirement benefits cannot be fully earned under the qualified retirement plans. See Note 10 to Financial Statements in our 2019 Form 10-K for additional information regarding pension plans.  OPEB Plans  We currently sponsor two OPEB plans. One plan covers our eligible current and future retirees whose services are 100% attributed to the regulated business. Effective January 1, 2018, we established a second plan to cover EFH Corp./Vistra retirees and eligible current and future retirees whose employment services were assigned to both Oncor (or a predecessor regulated utility business) and the non-regulated business of EFH Corp./Vistra. Vistra is solely responsible for its portion of the liability for retiree benefits related to those retirees. See Note 10 to Financial Statements in our 2019 Form 10-K for additional information.  Pension and OPEB Costs  Our net costs related to pension plans and the Oncor OPEB Plans for the three months ended March 31, 2020 and 2019 were comprised of the following:   Three Months Ended March 31,  2020 2019   Components of net allocated pension costs:  Service cost $ 8 $ 7  Interest cost 25 32  Expected return on assets (27) (30)  Amortization of net loss 12 7  Net pension costs 18 16  Components of net OPEB costs:  Service cost 1 2  Interest cost 8 11  Expected return on assets (2) (2)  Amortization of prior service cost (5) (5)  Amortization of net loss 3 4  Net OPEB costs 5 10  Total net pension and OPEB costs 23 26  Less amounts deferred principally as property or a regulatory asset (4) (7)  Net amounts recognized as operation and maintenance expense or other deductions $ 19 $ 19  The discount rates reflected in net pension and OPEB costs in 2020 are 3.12 % , 3.26% and 3.29% for the Oncor Retirement Plan, the Vistra Retirement Plan and the Oncor OPEB Plans, respectively. The expected return on pension and OPEB plan assets reflected in the 2020 cost amounts are 4.94% , 4.89% and 5.90% for the Oncor Retirement Plan, the Vistra Retirement Plan and the Oncor OPEB Plans, respectively.  Pension and OPEB Plans Cash Contributions  We made cash contributions to the pension plans and Oncor OPEB Plans of $13 million and $10 million, respectively, during the three months ended March 31, 2020. We expect to make additional cash contributions to the pension plans and Oncor OPEB Plans of $164 million and $25 million, respectively, during the remainder of 2020. Our aggregate pension plans and Oncor OPEB Plans funding is expected to total approximately $571 million and $176 million, respectively, in the five-year period 2020 to 2024 based on the latest actuarial projections.

Related-Party Transactions

Related-Party Transactions	3 Months Ended
	Mar. 31, 2020
Related-Party Transactions [Abstract]
RELATED-PARTY TRANSACTIONS	9. RELATED-PARTY TRANSACTIONS  The following represent our significant related-party transactions. As a result of the Sempra-Sharyland Transaction, Sharyland became a related party as of May 16, 2019.  · We are not a member of another entity’s consolidated tax group, but our owners’ federal income tax returns include their portion of our results. Under the terms of a tax sharing agreement among us, Oncor Holdings, Texas Transmission and STH (as successor to EFH Corp.), we are generally obligated to make payments to our owners, pro rata in accordance with their respective membership interests, in an aggregate amount that is substantially equal to the amount of federal income taxes that we would have been required to pay if we were filing our own corporate income tax return. STH will file a combined Texas margin tax return that includes our results and our share of Texas margin tax payments, which are accounted for as income taxes and calculated as if we were filing our own return. See discussion in Note 1 to Financial Statements in our 2019 Form 10-K under “Provision in Lieu of Income Taxes.” Under the “in lieu of” tax concept, all in lieu of tax assets and tax liabilities represent amounts that will eventually be settled with our members. In the event such amounts are not paid under the tax sharing agreement, it is probable that this regulatory liability will continue to be included in Oncor’s rate setting processes.  Amounts payable to (receivable from) members related to income taxes under the tax sharing agreement and reported on our balance sheets consisted of the following:   At March 31, 2020 At December 31, 2019  STH Texas Transmission Total STH Texas Transmission Total   Federal income taxes payable (receivable) $ 3 $ 1 $ 4 $ (2) $ (1) $ (3)  Texas margin taxes payable 28 - 28 22 - 22  Net payable (receivable) $ 31 $ 1 $ 32 $ 20 $ (1) $ 19  There were no cash payments made to (received from) members related to income taxes for the three months ended March 31, 2020 and 2019.  See Note 7 for information regarding distributions to and capital contributions from members.  · Sharyland provided wholesale transmission service to us in the amount of $3 million and we provided Sharyland with substation monitoring and switching services of less than $1 million in the three months ended March 31, 2020.

Supplementary Financial Informa

Supplementary Financial Information	3 Months Ended
	Mar. 31, 2020
Supplementary Financial Information [Abstract]
SUPPLEMENTARY FINANCIAL INFORMATION	10. SUPPLEMENTARY FINANCIAL INFORMATION  Other Deductions and (Income)   Three Months Ended March 31,  2020 2019   Professional fees $ 1 $ 3  Recoverable pension and OPEB - non-service costs 14 14  AFUDC equity income (5) -  Other, including interest income 3 -  Total other deductions and (income) - net $ 13 $ 17  Interest Expense and Related Charges   Three Months Ended March 31,  2020 2019   Interest $ 101 $ 88  Amortization of debt issuance costs and discounts 3 1  Less allowance for funds used during construction – capitalized interest portion (3) (3)  Total interest expense and related charges $ 101 $ 86  Trade Accounts and Other Receivables  Trade accounts and other receivables reported on our balance sheets consisted of the following:   At March 31, At December 31,  2020 2019   Gross trade accounts and other receivables $ 662 $ 666  Allowance for uncollectible accounts (6) (5)  Trade accounts receivable – net $ 656 $ 661  At both March 31 , 2020 and December 31, 2019, REP subsidiaries of our two largest customers represented 15% and 11% of the trade accounts receivable balance, respectively.  Under a PUCT rule relating to the Certification of Retail Electric Providers, write-offs of uncollectible amounts owed by REPs are deferred as a regulatory asset.  Investments and Other Property  Investments and other property reported on our balance sheets consisted of the following:    At March 31, At December 31,  2020 2019   Assets related to employee benefit plans $ 112 $ 119  Land 12 12  Other 2 2  Total investments and other property $ 126 $ 133 Property, Plant and Equipment  Property, plant and equipment - net reported on our balance sheets consisted of the following.   Composite Depreciation Rate/ At March 31, At December 31,  Avg. Life at March 31, 2020 2020 2019  Assets in service:  Distribution 2.8% / 35.9 years $ 14,211 $ 14,007  Transmission 2.9% / 35.0 years 11,201 11,094  Other assets 6.9% / 14.6 years 1,653 1,648  Total 27,065 26,749  Less accumulated depreciation 8,102 7,986  Net of accumulated depreciation 18,963 18,763  Construction work in progress 832 585  Held for future use 21 22  Property, plant and equipment – net $ 19,816 $ 19,370  Intangible Assets  Intangible assets (other than goodwill) reported on our balance sheets as part of property, plant and equipment consisted of the following:   At March 31, 2020 At December 31, 2019  Gross Gross  Carrying Accumulated Carrying Accumulated  Amount Amortization Net Amount Amortization Net   Identifiable intangible assets subject to amortization:  Land easements $ 576 $ 108 $ 468 $ 575 $ 107 $ 468  Capitalized software 937 444 493 933 430 503  Total $ 1,513 $ 552 $ 961 $ 1,508 $ 537 $ 971  A ggregate amortization expenses for intangible assets totaled $15 million and $13 million for the three months ended March 31, 2020 and 2019, respectively. The estimated aggregate amortization expense for each of the next five fiscal years is as follows:   Year Amortization Expense  2020 $ 61  2021 61  2022 61  2023 61  2024 60  Employee Benefit, Operating Lease and Other Obligations  Employee benefit, operating lease and other obligations reported on our balance sheets consisted of the following:   At March 31, At December 31,  2020 2019   Retirement plans and other employee benefits $ 1,810 $ 1,834  Operating lease liabilities 94 66  Investment tax credits 6 6  Other 88 74  Total employee benefit, operating lease and other obligations $ 1,998 $ 1,980  Supplemental Cash Flow Information   Three Months Ended March 31,  2020 2019   Cash payments (receipts) related to:  Interest $ 90 $ 56  Less capitalized interest (3) (3)  Interest payments (net of amounts capitalized) $ 87 $ 53   Noncash increase in operating lease obligations for ROU assets $ 37 $ 88   Noncash construction expenditures (a) $ 221 $ 168 ____________ (a) Represents end-of-period accruals.

Infrareit Acquisition

Infrareit Acquisition	3 Months Ended
	Mar. 31, 2020
Infrareit Acquisition [Abstract]
INFRAREIT ACQUISITION	11. INFRAREIT ACQUISITION  On May 16, 2019, we completed the InfraREIT Acquisition, pursuant to which we acquired all of the equity interests of InfraREIT and its subsidiary, InfraREIT Partners. In connection with and immediately following the closing of the InfraREIT Acquisition, on May 16, 2019, we extinguished all outstanding debt of InfraREIT and its subsidiaries through repaying $602 million principal amount of InfraREIT subsidiary debt and exchanging $351 million principal amount of InfraREIT subsidiary debt for new Oncor senior secured debt.  The assets we acquired include approximately 1,575 miles of transmission lines, including 1,235 circuit miles of 345k V transmission lines and approximately 340 circuit miles of 138kV transmission lines. The north, central, and west Texas transmission system acquired by us in the transaction is directly connected to approximately 20 operational generation facilities totaling approximately 3,900 MW and serves over 50 substations.  Business Combination Accounting  We accounted for the InfraREIT Acquisition as a business acquisition with identifiable assets acquired and liabilities assumed recorded at their estimated fair values on the closing date. The combined results of operations are reported in our condensed consolidated financial statements beginning as of the closing date.  The following table sets forth the final purchase price paid. In the three months ended March 31, 2020, we made no material purchase price allocation adjustments. The final purchase price allocation was completed as of March 31, 2020.     Purchase of outstanding InfraREIT shares and units $ 1,275  Certain transaction costs of InfraREIT paid by Oncor (a) 49  Total purchase price paid $ 1,324 __________________ (a) Represents certain transaction costs incurred by InfraREIT in connection with the transaction and paid by Oncor, including a $40 million management termination fee payable to an affiliate of Hunt Consolidated, Inc.  Unaudited Pro Forma Financial Information  The following unaudited pro forma financial information for the three months ended March 31, 2019 assumes that the InfraREIT Acquisition occurred on January 1, 2018. The unaudited pro forma financial information is provided for information purposes only and is not necessarily indicative of the results of operations that would have occurred had the InfraREIT Acquisition been completed on January 1, 2018, nor is the unaudited pro forma financial information indicative of future results of operations, which may differ materially from the pro forma financial information presented here.   Three Months Ended March 31,  2019  Oncor Consolidated Pro Forma Revenues $ 1,072  The unaudited pro forma financial information above excludes pro forma earnings due to the impracticability of a calculation. The acquiree previously operated under a real estate investment trust structure with a unique cost structure and unique federal tax attributes. An accurate retrospective application cannot be objectively and reliably calculated as the new cost structure and new tax attributes would require a significant amount of estimates and judgments.

Business And Significant Acco_2

Business And Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2020
Business And Significant Accounting Policies [Abstract]
Description Of Business	Description of Business  References in this report to “we,” “our,” “us” and “the company” are to Oncor and/or its subsidiaries as apparent in the context. See “Glossary” for definition of terms and abbreviations.  We are a regulated electricity transmission and distribution company principally engaged in providing delivery services to REPs that sell power in the north-central, eastern, western and panhandle regions of Texas. We are a direct, majority-owned subsidiary of Oncor Holdings, which is indirectly and wholly owned by Sempra. Oncor Holdings owns 80.25% of our outstanding membership interests and Texas Transmission owns 19.75% of our outstanding membership interests. We are managed as an integrated business; consequently, there is only one reportable segment.  Our condensed consolidated financial statements for the three months ended March 31, 2020, include the results of our wholly owned indirect subsidiary, NTU, which is a regulated utility that provides electricity transmission delivery service in the north-central, western and panhandle regions of Texas. We acquired NTU as part of the InfraREIT Acquisition that closed on May 16, 2019.  Ring-Fencing Measures  Since 2007, various ring-fencing measures have been taken to enhance our credit quality and the separateness between the Oncor Ring-Fenced Entities and entities with ownership interests in Oncor or Oncor Holdings. These ring-fencing measures serve to mitigate the Oncor Ring-Fenced Entities’ credit exposure to owners of Oncor and Oncor Holdings, and to reduce the risk that the assets and liabilities of Oncor Ring-Fenced Entities would be substantively consolidated with the assets and liabilities of any direct or indirect owners of Oncor and Oncor Holdings in connection with a bankruptcy of any such entities. These measures include the November 2008 sale of 19.75% of Oncor’s equity interests to Texas Transmission.  In March 2018, Sempra indirectly acquired Oncor Holdings through the Sempra Acquisition. The Sempra Acquisition was consummated after obtaining the approval of the bankruptcy court in the EFH Bankruptcy Proceedings and the PUCT. The PUCT approval was obtained in Docket No. 47675, and the final order issued in that docket (Sempra Order) outlines certain ring-fencing measures, governance mechanisms and restrictions that apply after the Sempra Acquisition. As a result of these ring-fencing measures, Sempra does not control Oncor, and the ring-fencing measures limit Sempra’s ability to direct the management, policies and operations of Oncor, including the deployment or disposition of Oncor’s assets, declarations of dividends, strategic planning and other important corporate issues and actions.  None of the assets of the Oncor Ring-Fenced Entities are available to satisfy the debt or obligations of any Sempra entity or any other direct or indirect owner of Oncor or Oncor Holdings. The assets and liabilities of the Oncor Ring-Fenced Entities are separate and distinct from those of any Sempra entities and any other direct or indirect owner of Oncor or Oncor Holdings. We do not bear any liability for debt or contractual obligations of Sempra and its affiliates or any other direct or indirect owner of Oncor or Oncor Holdings, and vice versa. Accordingly, our operations are conducted, and our cash flows are managed, independently from Sempra and its affiliates and any other direct or indirect owner of Oncor or Oncor Holdings.  Oncor is a limited liability company governed by a board of directors, not its members. The Sempra Order and our Limited Liability Company Agreement require that the board of directors of Oncor consist of thirteen members, constituted as follows:  · seven Disinterested Directors, who (i) shall be independent directors in all material respects under the rules of the New York Stock Exchange in relation to Sempra or its subsidiaries and affiliated entities and any entity with a direct or indirect ownership interest in Oncor or Oncor Holdings, and (ii) shall have no material relationship with Sempra or its subsidiaries or affiliated entities or any entity with a direct or indirect ownership interest in Oncor or Oncor Holdings, currently or within the previous ten years; · two members designated by Sempra (through Oncor Holdings); · two members designated by Texas Transmission; and · two current or former officers of Oncor (the Oncor Officer Directors), currently Robert S. Shapard and E. Allen Nye, Jr., who are our Chairman of the Board and Chief Executive, respectively.  In order for a current or former officer of Oncor to be eligible to serve as an Oncor Officer Director, the officer cannot have worked for Sempra or any of its affiliates (excluding Oncor Holdings and Oncor) or any other entity with a direct or indirect ownership interest in Oncor or Oncor Holdings in the ten-year period prior to the officer being employed by Oncor. Oncor Holdings, at the direction of STIH, has the right to nominate and/or seek the removal of the Oncor Officer Directors, subject to approval by a majority of the Oncor board of directors. STIH is a wholly owned indirect subsidiary of, and controlled by, Sempra following the Sempra Acquisition.  In addition, the Sempra Order provides that Oncor’s board cannot be overruled by the board of Sempra or any of its subsidiaries on dividend policy, the issuance of dividends or other distributions (except for contractual tax payments), debt issuance, capital expenditures, operation and maintenance expenditures, management and service fees, and appointment or removal of board members, provided that certain actions may also require the additional approval of the Oncor Holdings board of directors. The Sempra Order also provides that any changes to the size, composition, structure or rights of the board must first be approved by the PUCT. In addition, if Sempra acquires Texas Transmission’s interest in Oncor, the two board positions on Oncor’s board of directors that Texas Transmission is entitled to appoint will be eliminated and the size of Oncor’s board of directors will be reduced by two.  Additional regulatory commitments, governance mechanisms and restrictions provided in the Sempra Order and our Limited Liability Company Agreement to ring-fence Oncor from its owners include, among others:  · A majority of the Disinterested Directors of Oncor must approve any annual or multi-year budget if the aggregate amount of capital expenditures or operating and maintenance expenditures in such budget is more than a 10% increase or decrease from the corresponding amounts of such expenditures in the budget for the preceding fiscal year or multi-year period, as applicable;  · Oncor may not pay any dividends or make any other distributions (except for contractual tax payments) if a majority of its Disinterested Directors determines that it is in the best interests of Oncor to retain such amounts to meet expected future requirements;  · At all times, Oncor will remain in compliance with the debt-to-equity ratio established by the PUCT from time to time for ratemaking purposes, and Oncor will not pay dividends or other distributions (except for contractual tax payments), if that payment would cause its debt-to-equity ratio to exceed the debt-to-equity ratio approved by the PUCT;  · If the credit rating on Oncor’s senior secured debt by any of the three major rating agencies falls below BBB (or the equivalent), Oncor will suspend dividends and other distributions (except for contractual tax payments), unless otherwise allowed by the PUCT;  · Without the prior approval of the PUCT, neither Sempra nor any of its affiliates (excluding Oncor) will incur, guaranty or pledge assets in respect of any indebtedness that is dependent on the revenues of Oncor in more than a proportionate degree than the other revenues of Sempra or on the stock of Oncor, and there will be no debt at STH or STIH at any time following the closing of the Sempra Acquisition;  · Neither Oncor nor Oncor Holdings will lend money to or borrow money from Sempra or any of its affiliates (other than Oncor subsidiaries), or any entity with a direct or indirect ownership interest in Oncor or Oncor Holdings, and neither Oncor nor Oncor Holdings will share credit facilities with Sempra or any of its affiliates (other than Oncor subsidiaries), or any entity with a direct or indirect ownership interest in Oncor or Oncor Holdings;  · There must be maintained certain “separateness measures” that reinforce the financial separation of Oncor from its owners, including a requirement that dealings between Oncor, Oncor Holdings and their subsidiaries with Sempra, any of Sempra’s other affiliates or any entity with a direct or indirect ownership interest in Oncor or Oncor Holdings, must be on an arm’s-length basis, limitations on affiliate transactions, separate recordkeeping requirements and a prohibition on Sempra or its affiliates pledging Oncor assets or stock for any entity other than Oncor; and  · Sempra will continue to hold indirectly at least 51% of the ownership interests in Oncor and Oncor Holdings for at least five years following the closing of the Sempra Acquisition, unless otherwise specifically authorized by the PUCT. 
Basis Of Presentation	Basis of Presentation  These unaudited condensed consolidated financial statements should be read in conjunction with the audited financial statements and related notes included in our 2019 Form 10-K. In the opinion of Oncor management, all adjustments (consisting of normal recurring accruals) necessary for a fair presentation of the results of operations and financial position have been made. We have evaluated all subsequent events through the date the financial statements were issued. All appropriate intercompany items and transactions have been eliminated in consolidation. The results of operations for an interim period may not give a true indication of results for a full year due to seasonality (see Note 13 to Financial Statements in our 2019 Form 10-K for additional information regarding quarterly results of operations).  Our consolidated financial statements have been prepared in accordance with GAAP governing rate-regulated operations. All dollar amounts in the financial statements and tables in the notes are stated in millions of U.S. dollars unless otherwise indicated.
Use Of Estimates	Use of Estimates  Preparation of our financial statements requires management to make estimates and assumptions about future events that affect the reporting of assets and liabilities at the balance sheet dates and the reported amounts of revenue and expense, including fair value measurements. In the event estimates and/or assumptions prove to be different from actual amounts, adjustments are made in subsequent periods to reflect more current information. No material adjustments were made to previous estimates or assumptions during the current period.
Interest Rate Derivatives And Hedge Accounting	Interest Rate Derivatives and Hedge Accounting  We are exposed to interest rates primarily as a result of our current and expected use of financing. We may, from time to time, utilize interest rate derivative instruments typically designated as cash flow hedges, to lock in interest rates in anticipation of future financings. We may designate an interest rate derivative instrument as a cash flow hedge if it effectively converts anticipated cash flows associated with interest payments to a fixed dollar amount. In accounting for cash flow hedges, derivative assets and liabilities are recorded on the balance sheet at fair value with an offset to other comprehensive income. Amounts remain in accumulated other comprehensive income and are reclassified into net income as the interest expense on the related debt affects net income. See Note 5 for details on our interest rate hedging activity.
Impairment Of Long-Lived Assets And Goodwill	Impairment of Long-Lived Assets and Goodwill  We evaluate long-lived assets (including intangible assets with finite lives) for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable.  We also evaluate goodwill for impairment annually on October 1 and whenever events or changes in circumstances indicate that an impairment may exist. The determination of the existence of these and other indications of impairment involves judgments that are subjective in nature and may require the use of estimates in forecasting future results and cash flows.
Changes In Accounting Standards	Changes in Accounting Standards  Topic 326, “Financial Instruments—Credit Losses” – In June 2016 the FASB issued ASU No. 2016-13, which changes how entities account for credit losses on receivables and certain other financial assets. The guidance requires use of a current expected credit loss model, which may result in earlier recognition of credit losses than under previous accounting standards. We adopted the new standard effective January 1, 2020. The adoption of the new standard did not have a material impact on our consolidated financial statements.  Topic 848, “Facilitation of the Effects of Reference Rate Reform on Financial Reporting” – In March 2020 the FASB issued ASU No. 2020-04, which provides optional expedients and exceptions for applying GAAP to contracts, hedging relationships, and other transactions that reference LIBOR or another reference rate expected to be discontinued because of reference rate reform. ASU No. 2020-04 is effective for all entities as of March 12, 2020 through December 31, 2022. The standard allows entities to account for contract modifications as an event that does not require reassessment or remeasurement (i.e., as a continuation of the existing contract). We are currently evaluating the optional expedients and exceptions under the standard. 

Regulatory Matters (Tables)

Regulatory Matters (Tables)	3 Months Ended
	Mar. 31, 2020
Regulatory Matters [Abstract]
Components Of Regulatory Assets And Liabilities	    Remaining Rate Recovery/ Amortization Period  At March 31, 2020 At March 31, 2020 At December 31, 2019  Regulatory assets:  Employee retirement liability (a)(b)(c) To be determined $ 615 $ 623  Employee retirement costs being amortized 8 years 253 262  Employee retirement costs incurred since the last rate review period (b) To be determined 76 79  Self-insurance reserve (primarily storm recovery costs) being amortized 8 years 298 309  Self-insurance reserve incurred since the last rate review period (primarily storm related) (b) To be determined 221 238  Securities reacquisition costs Lives of related debt 27 29  Deferred conventional meter and metering facilities depreciation 1 year 10 15  Under-recovered AMS costs 8 years 165 170  Energy efficiency performance bonus (a) 1 year or less 7 9  Wholesale distribution substation service To be determined 39 34  Other regulatory assets (d) Various 9 7  Total regulatory assets 1,720 1,775   Regulatory liabilities:  Estimated net removal costs Lives of related assets 1,199 1,178  Excess deferred taxes Primarily over lives of related assets 1,557 1,574  Over-recovered wholesale transmission service expense (a) 1 year or less 14 30  Other regulatory liabilities Various 16 11  Total regulatory liabilities 2,786 2,793  Net regulatory assets (liabilities) $ (1,066) $ (1,018) ____________ (a) Not earning a return in the regulatory rate-setting process. (b) Recovery is specifically authorized by statute or by the PUCT, subject to reasonableness review. (c) Represents unfunded liabilities recorded in accordance with pension and OPEB accounting standards. (d) Includes $1 million in regulatory assets established to track our incremental costs related to the impact of COVID-19, including costs relating to our pandemic response plan.

Revenues (Tables)

Revenues (Tables)	3 Months Ended
	Mar. 31, 2020
Revenues [Abstract]
Disaggregation Of Revenues	  Three Months Ended March 31,  2020 2019  Operating revenues  Revenues contributing to earnings:  Distribution base revenues $ 496 $ 499  Transmission base revenues (TCOS revenues):  Billed to third-party wholesale customers 196 143  Billed to REPs serving Oncor distribution customers, through TCRF 109 85  Total transmission base revenues 305 228  Other miscellaneous revenues 16 17  Total revenues contributing to earnings 817 744   Revenues collected for pass-through expenses:  TCRF - third-party wholesale transmission service 245 260  EECRF and other regulatory charges 10 12  Revenues collected for pass-through expenses 255 272   Total operating revenues $ 1,072 $ 1,016 

Short-Term Borrowings (Tables)

Short-Term Borrowings (Tables)	3 Months Ended
	Mar. 31, 2020
Short-Term Borrowings [Abstract]
Schedule Of Short-Term Borrowings	  At March 31, At December 31,  2020 2019  Total credit facility borrowing capacity $ 2,000 $ 2,000  Commercial paper outstanding (a) - (46)  Credit facility outstanding (b) - -  Letters of credit outstanding (c) (9) (10)  Available unused credit $ 1,991 $ 1,944 ____________ a) The weighted average interest rate for commercial paper was 1.84% at December 31, 2019. b) At March 31, 2020, the applicable interest rate for any outstanding borrowings was LIBOR plus 1.00%. c) The interest rate on outstanding letters of credit at both March 31, 2020 and December 31, 2019 was 1.20% based on our credit ratings.

Long-Term Debt (Tables)

Long-Term Debt (Tables)	3 Months Ended
	Mar. 31, 2020
Long-Term Debt [Abstract]
Schedule Of Long-Term Debt	  March 31, December 31,  2020 2019  Fixed Rate Secured:  5.75% Senior Notes due September 30, 2020 $ 126 $ 126  8.50% Senior Notes, Series C, due December 30, 2020 13 14  4.10% Senior Notes, due June 1, 2022 400 400  7.00% Debentures due September 1, 2022 482 482  2.75% Senior Notes due June 1, 2024 500 500  2.95% Senior Notes due April 1, 2025 350 350  3.86% Senior Notes, Series A, due December 3, 2025 174 174  3.86% Senior Notes, Series B, due January 14, 2026 38 38  3.70% Senior Notes due November 15, 2028 650 650  5.75% Senior Notes due March 15, 2029 318 318  7.25% Senior Notes, Series B, due December 30, 2029 36 36  2.75% Senior Notes due May 15, 2030 400 -  6.47% Senior Notes, Series A, due September 30, 2030 82 83  7.00% Senior Notes due May 1, 2032 500 500  7.25% Senior Notes due January 15, 2033 350 350  7.50% Senior Notes due September 1, 2038 300 300  5.25% Senior Notes due September 30, 2040 475 475  4.55% Senior Notes due December 1, 2041 400 400  5.30% Senior Notes due June 1, 2042 500 500  3.75% Senior Notes due April 1, 2045 550 550  3.80% Senior Notes due September 30, 2047 325 325  4.10% Senior Notes due November 15, 2048 450 450  3.80% Senior Notes, due June 1, 2049 500 500  3.10% Senior Notes, due September 15, 2049 700 700  3.70% Senior Notes due May 15, 2050 400 -  Secured long-term debt 9,019 8,221  Unsecured:  Term loan credit agreement maturing October 6, 2020 - 460  Term loan credit agreement maturing June 1, 2021 450 -  Total long-term debt 9,469 8,681  Unamortized discount and debt issuance costs (65) (56)  Less amount due currently (148) (608)  Long-term debt, less amounts due currently $ 9,256 $ 8,017 
Schedule Of Long-Term Debt Maturity	  Year Amount  2020 (excluding first three months of 2020) $ 148  2021 459  2022 891  2023 10  2024 510  Thereafter 7,451  Unamortized discount and debt issuance costs (65)  Total $ 9,404 

Commitments And Contingencies (

Commitments And Contingencies (Tables)	3 Months Ended
	Mar. 31, 2020
Commitments And Contingencies [Abstract]
Schedule Of Operating Lease Maturity	  Year Amount  2020 (remaining nine months) $ 23  2021 28  2022 24  2023 18  2024 12  Thereafter 28  Total undiscounted lease payments 133  Less imputed interest (12)  Total future minimum lease payments $ 121 

Membership Interests (Tables)

Membership Interests (Tables)	3 Months Ended
	Mar. 31, 2020
Membership Interests [Abstract]
Schedule Of Changes To Membership Interests	  Capital Accounts Accumulated Other Comprehensive Income (Loss) Total Membership Interests  Three Months Ended March 31, 2020  Balance at December 31, 2019 $ 10,938 $ (139) $ 10,799  Net income 131 - 131  Distributions (91) - (91)  Capital contributions 87 - 87  Net effects of cash flow hedges (Note 5) - (23) (23)  Defined benefit pension plans - 1 1  Balance at March 31, 2020 $ 11,065 $ (161) $ 10,904     Capital Accounts Accumulated Other Comprehensive Income (Loss) Total Membership Interests  Three Months Ended March 31, 2019  Balance at December 31, 2018 $ 8,624 $ (164) $ 8,460  Net income 116 - 116  Distributions (71) - (71)  Capital contributions 70 - 70  Net effects of cash flow hedges 4 (4) -  Defined benefit pension plans - 1 1  Balance at March 31, 2019 $ 8,743 $ (167) $ 8,576 
Schedule Of Changes To Accumulated Other Comprehensive Income (Loss)	  Cash Flow Hedges – Interest Rate Swaps Defined Benefit Pension and OPEB Plans Accumulated Other Comprehensive Income (Loss)  Balance at December 31, 2019 $ (18) $ (121) $ (139)  Defined benefit pension plans - 1 1  Cash flow hedges — net decrease in fair value of derivatives (net of tax benefit of $6 ) (Note 5) (23) - (23)  Balance at March 31, 2020 $ (41) $ (120) $ (161)   Balance at December 31, 2018 $ (16) $ (148) $ (164)  Defined benefit pension plans - 1 1  Amounts reclassified from accumulated other comprehensive income (loss) to capital account (4) - (4)  Balance at March 31, 2019 $ (20) $ (147) $ (167) 

Pension And OPEB Plans (Tables)

Pension And OPEB Plans (Tables)	3 Months Ended
	Mar. 31, 2020
Pension And OPEB Plans [Abstract]
Schedule Of Pension And OPEB Plan Costs	  Three Months Ended March 31,  2020 2019   Components of net allocated pension costs:  Service cost $ 8 $ 7  Interest cost 25 32  Expected return on assets (27) (30)  Amortization of net loss 12 7  Net pension costs 18 16  Components of net OPEB costs:  Service cost 1 2  Interest cost 8 11  Expected return on assets (2) (2)  Amortization of prior service cost (5) (5)  Amortization of net loss 3 4  Net OPEB costs 5 10  Total net pension and OPEB costs 23 26  Less amounts deferred principally as property or a regulatory asset (4) (7)  Net amounts recognized as operation and maintenance expense or other deductions $ 19 $ 19 

Related-Party Transactions (Tab

Related-Party Transactions (Tables)	3 Months Ended
	Mar. 31, 2020
Related-Party Transactions [Abstract]
Schedule Of Trade Accounts And Other Receivables From Related Parties	  At March 31, 2020 At December 31, 2019  STH Texas Transmission Total STH Texas Transmission Total   Federal income taxes payable (receivable) $ 3 $ 1 $ 4 $ (2) $ (1) $ (3)  Texas margin taxes payable 28 - 28 22 - 22  Net payable (receivable) $ 31 $ 1 $ 32 $ 20 $ (1) $ 19 

Supplementary Financial Infor_2

Supplementary Financial Information (Tables)	3 Months Ended
	Mar. 31, 2020
Supplementary Financial Information [Abstract]
Schedule Of Other Deductions And (Income)	  Three Months Ended March 31,  2020 2019   Professional fees $ 1 $ 3  Recoverable pension and OPEB - non-service costs 14 14  AFUDC equity income (5) -  Other, including interest income 3 -  Total other deductions and (income) - net $ 13 $ 17 
Schedule Of Interest Expense And Related Charges	  Three Months Ended March 31,  2020 2019   Interest $ 101 $ 88  Amortization of debt issuance costs and discounts 3 1  Less allowance for funds used during construction – capitalized interest portion (3) (3)  Total interest expense and related charges $ 101 $ 86 
Schedule Of Trade Accounts And Other Receivables	  At March 31, At December 31,  2020 2019   Gross trade accounts and other receivables $ 662 $ 666  Allowance for uncollectible accounts (6) (5)  Trade accounts receivable – net $ 656 $ 661 
Summary of Investments And Other Property	  At March 31, At December 31,  2020 2019   Assets related to employee benefit plans $ 112 $ 119  Land 12 12  Other 2 2  Total investments and other property $ 126 $ 133 
Schedule Of Property, Plant And Equipment	  Composite Depreciation Rate/ At March 31, At December 31,  Avg. Life at March 31, 2020 2020 2019  Assets in service:  Distribution 2.8% / 35.9 years $ 14,211 $ 14,007  Transmission 2.9% / 35.0 years 11,201 11,094  Other assets 6.9% / 14.6 years 1,653 1,648  Total 27,065 26,749  Less accumulated depreciation 8,102 7,986  Net of accumulated depreciation 18,963 18,763  Construction work in progress 832 585  Held for future use 21 22  Property, plant and equipment – net $ 19,816 $ 19,370 
Schedule Of Intangible Assets	  At March 31, 2020 At December 31, 2019  Gross Gross  Carrying Accumulated Carrying Accumulated  Amount Amortization Net Amount Amortization Net   Identifiable intangible assets subject to amortization:  Land easements $ 576 $ 108 $ 468 $ 575 $ 107 $ 468  Capitalized software 937 444 493 933 430 503  Total $ 1,513 $ 552 $ 961 $ 1,508 $ 537 $ 971 
Schedule Of Estimated Aggregate Amortization Expenses	  Year Amortization Expense  2020 $ 61  2021 61  2022 61  2023 61  2024 60 
Schedule Of Employee Benefit Obligations And Other	  At March 31, At December 31,  2020 2019   Retirement plans and other employee benefits $ 1,810 $ 1,834  Operating lease liabilities 94 66  Investment tax credits 6 6  Other 88 74  Total employee benefit, operating lease and other obligations $ 1,998 $ 1,980 
Schedule Of Supplemental Cash Flow Information	  Three Months Ended March 31,  2020 2019   Cash payments (receipts) related to:  Interest $ 90 $ 56  Less capitalized interest (3) (3)  Interest payments (net of amounts capitalized) $ 87 $ 53   Noncash increase in operating lease obligations for ROU assets $ 37 $ 88   Noncash construction expenditures (a) $ 221 $ 168 ____________ (a) Represents end-of-period accruals.

Infrareit Acquisition (Tables)

Infrareit Acquisition (Tables)	3 Months Ended
	Mar. 31, 2020
Infrareit Acquisition [Abstract]
Total Purchase Price Paid	  Purchase of outstanding InfraREIT shares and units $ 1,275  Certain transaction costs of InfraREIT paid by Oncor (a) 49  Total purchase price paid $ 1,324 __________________ (a) Represents certain transaction costs incurred by InfraREIT in connection with the transaction and paid by Oncor, including a $40 million management termination fee payable to an affiliate of Hunt Consolidated, Inc.
Pro Forma Information	  Three Months Ended March 31,  2019  Oncor Consolidated Pro Forma Revenues $ 1,072 

Business And Significant Acco_3

Business And Significant Accounting Policies (Narrative) (Details) $ in Millions	3 Months Ended
	Mar. 31, 2020USD ($)entity	Dec. 31, 2019USD ($)
Business And Significant Accounting Polices [Line Items]
Number of board of directors	13
Number of disinterested directors	7
Direct or indirect ownership interest time period	10 years
Number of board positions to be eliminated upon acquisition	2
Goodwill | $	$ 4,740	$ 4,740
Operating lease obligations | $	$ 121
Oncor Holdings [Member]
Business And Significant Accounting Polices [Line Items]
Number of disinterested directors	2
Texas Transmission [Member]
Business And Significant Accounting Polices [Line Items]
Number of disinterested directors	2
Sempra Energy [Member]
Business And Significant Accounting Polices [Line Items]
Number of disinterested directors	2
Oncor Holdings [Member]
Business And Significant Accounting Polices [Line Items]
Ownership	80.25%
Oncor Holdings [Member] | Sempra Energy [Member]
Business And Significant Accounting Polices [Line Items]
Percentage of membership interest owned by non-controlling owners	51.00%
Ownership holding period	5 years
Texas Transmission [Member]
Business And Significant Accounting Polices [Line Items]
Percentage of membership interest owned by non-controlling owners	19.75%
Minimum [Member]
Business And Significant Accounting Polices [Line Items]
Disinterested directors expenditure budget percentage	10.00%

Regulatory Matters (Narrative)

Regulatory Matters (Narrative) (Details) $ in Millions	3 Months Ended
	Mar. 31, 2020USD ($)$ / MWh
Regulatory Matters [Abstract]
Regulatory capitalization ratio, debt	57.50%
Regulatory capitalization ratio, equity	42.50%
Per MWh surcharge to be collected | $ / MWh	0.33
Aggregate amount of loans available due to COVID-19 | $	$ 15

Regulatory Matters (Components

Regulatory Matters (Components Of Regulatory Assets And Liabilities) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Regulatory Assets And Liabilities [Line Items]
Carrying Amount, Regulatory Assets	$ 1,720	$ 1,775
Carrying Amount, Regulatory Liabilities	2,786	2,793
Net regulatory assets (liabilities)	$ (1,066)	(1,018)
Estimated Net Removal Costs [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period	Lives of related assets
Carrying Amount, Regulatory Liabilities	$ 1,199	1,178
Excess Deferred Taxes [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period	Primarily over lives of related assets
Carrying Amount, Regulatory Liabilities	$ 1,557	1,574
Over-Recovered Wholesale Transmission Service Expense [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period	1 year or less
Carrying Amount, Regulatory Liabilities	$ 14	30
Other Regulatory Liabilities [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period	Various
Carrying Amount, Regulatory Liabilities	$ 16	11
Employee Retirement Liability [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period	To be determined
Carrying Amount, Regulatory Assets	$ 615	623
Employee Retirement Costs Being Amortized [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period	8 years
Carrying Amount, Regulatory Assets	$ 253	262
Employee Retirement Costs Incurred Since The Last Rate Review Period [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period	To be determined
Carrying Amount, Regulatory Assets	$ 76	79
Self-Insurance Reserve (Primarily Storm Recovery Costs) Being Amortized [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period	8 years
Carrying Amount, Regulatory Assets	$ 298	309
Self-Insurance Reserve Incurred Since The Last Rate Review Period (Primarily Storm Related) [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period	To be determined
Carrying Amount, Regulatory Assets	$ 221	238
Securities Reacquisition Costs [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period	Lives of related debt
Carrying Amount, Regulatory Assets	$ 27	29
Deferred Conventional Meter And Metering Facilities Depreciation [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period	1 year
Carrying Amount, Regulatory Assets	$ 10	15
Under-recovered AMS Costs [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period	8 years
Carrying Amount, Regulatory Assets	$ 165	170
Energy Efficiency Performance Bonus [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period	1 year or less
Carrying Amount, Regulatory Assets	$ 7	9
Wholesale Distribution Substation Service [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period	To be determined
Carrying Amount, Regulatory Assets	$ 39	34
Other Regulatory Assets [Member]
Regulatory Assets And Liabilities [Line Items]
Remaining Rate Recovery/Amortization Period	Various
Carrying Amount, Regulatory Assets	$ 9	$ 7
Impact Of COVID-19 [Member]
Regulatory Assets And Liabilities [Line Items]
Carrying Amount, Regulatory Assets	$ 1

Revenues (Narrative) (Details)

Revenues (Narrative) (Details)	3 Months Ended
	Mar. 31, 2020itementity
Disaggregation of Revenue [Line Items]
Number of REPS | item	90
Number of counterparties | entity	2
Payment term	35 days
REP Subsidiary One [Member] | Revenue Benchmark [Member]
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	25.00%
REP Subsidiary Two [Member] | Revenue Benchmark [Member]
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	18.00%

Revenues (Disaggregation Of Rev

Revenues (Disaggregation Of Revenues) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Disaggregation of Revenue [Line Items]
Total revenues contributing to earnings	$ 817	$ 744
Revenues collected for pass-through expenses	255	272
Total operating revenues	1,072	1,016
Distribution Base Revenues [Member]
Disaggregation of Revenue [Line Items]
Total revenues contributing to earnings	496	499
Transmission Base Revenues (TCOS Revenues) [Member]
Disaggregation of Revenue [Line Items]
Total revenues contributing to earnings	305	228
Transmission Base Revenues (TCOS Revenues) [Member] | Third-Party Wholesale Customers [Member]
Disaggregation of Revenue [Line Items]
Total revenues contributing to earnings	196	143
Transmission Base Revenues (TCOS Revenues) [Member] | REPS Serving Oncor Distribution Customers, Through TCRF [Member]
Disaggregation of Revenue [Line Items]
Total revenues contributing to earnings	109	85
Other Miscellaneous Revenues [Member]
Disaggregation of Revenue [Line Items]
Total revenues contributing to earnings	16	17
TCRF - Third-party Wholesale Transmission Service [Member]
Disaggregation of Revenue [Line Items]
Revenues collected for pass-through expenses	245	260
EECRF And Other Regulatory Charges [Member]
Disaggregation of Revenue [Line Items]
Revenues collected for pass-through expenses	$ 10	$ 12

Short-Term Borrowings (Narrativ

Short-Term Borrowings (Narrative) (Details)	3 Months Ended
	Mar. 31, 2020USD ($)contractitementity	Mar. 23, 2020USD ($)	Dec. 31, 2019USD ($)	Mar. 31, 2018USD ($)	Nov. 30, 2017USD ($)
Line of Credit Facility [Line Items]
Borrowing capacity available under the credit facility	$ 2,000,000,000		$ 2,000,000,000
Letter of Credit [Member]
Line of Credit Facility [Line Items]
Outstanding borrowing under the revolving credit facility	$ 9,000,000		10,000,000
Credit Facility [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity					$ 2,000,000,000
Number of revolving credit facilities extension options | contract	2
Extension period for revolving line of credit	1 year
Credit facility, term	5 years
Expiration of revolving credit facility	Nov. 1, 2022
Credit Facility [Member] | Maximum [Member]
Line of Credit Facility [Line Items]
Possible additional increase in borrowing capacity amount					400,000,000
Credit Facility [Member] | Minimum [Member]
Line of Credit Facility [Line Items]
Possible additional increase in borrowing capacity amount					$ 100,000,000
Commercial Paper [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity				$ 2,000,000,000
Outstanding borrowing under the revolving credit facility			$ 46,000,000
Term Loan [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity		$ 350,000,000
Expiration of revolving credit facility	Mar. 22, 2021
Extension credit facility expiration date	Sep. 24, 2021
Outstanding borrowing under the revolving credit facility	$ 0
Number of possible withdraws from credit facility | item	4
Number of possible additional lenders | entity	1
Term Loan [Member] | Maximum [Member]
Line of Credit Facility [Line Items]
Possible additional increase in borrowing capacity amount		100,000,000
Term Loan [Member] | Minimum [Member]
Line of Credit Facility [Line Items]
Possible additional increase in borrowing capacity amount		$ 50,000,000
London Interbank Offered Rate (LIBOR) [Member] | Term Loan [Member]
Line of Credit Facility [Line Items]
Spread over variable rate	0.675%
Federal Funds Effective Rate [Member] | Term Loan [Member]
Line of Credit Facility [Line Items]
Spread over variable rate	0.50%
One-Month London Interbank Offered Rate [Member]
Line of Credit Facility [Line Items]
Spread over variable rate	1.00%
One-Month London Interbank Offered Rate [Member] | Term Loan [Member]
Line of Credit Facility [Line Items]
Spread over variable rate	1.00%

Short-Term Borrowings (Schedule

Short-Term Borrowings (Schedule Of Short-Term Borrowings) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Short-term Debt [Line Items]
Total credit facility borrowing capacity	$ 2,000	$ 2,000
Available unused credit	1,991	1,944
Commercial Paper [Member]
Short-term Debt [Line Items]
Outstanding		$ (46)
Weighted average interest rate		1.84%
Letter of Credit [Member]
Short-term Debt [Line Items]
Outstanding	$ (9)	$ (10)
Weighted average interest rate	1.20%	1.20%
One-Month London Interbank Offered Rate [Member]
Short-term Debt [Line Items]
Spread over variable rate	1.00%

Long-Term Debt (Narrative) (Det

Long-Term Debt (Narrative) (Details) $ in Millions	3 Months Ended
	Mar. 31, 2020USD ($)item	Mar. 16, 2020USD ($)	Feb. 28, 2020USD ($)	Jan. 29, 2020USD ($)	Dec. 31, 2019USD ($)
Long-Term Debt [Line Items]
Repayments of long-term debt	$ 462
Accumulated other comprehensive loss relassified to net income	4
Loss on interest rate hedge	29
Loss on interest rate hedge, after tax	23
Estimated fair value of our long-term debt including current maturities	10,734				$ 10,003
Carrying amount	$ 9,404				8,625
One-Month London Interbank Offered Rate [Member]
Long-Term Debt [Line Items]
Spread over variable rate	1.00%
2030 And 2050 Notes [Member]
Long-Term Debt [Line Items]
Proceeds from sale of Notes	$ 790
Increase in basis points per annum	0.50%
Term Loan Credit Agreement Maturing June 1, 2021 [Member]
Long-Term Debt [Line Items]
Number of possible withdraws from credit facility | item	4
Outstanding borrowing under the revolving credit facility		$ 232	$ 55	$ 163
Term Loan Credit Agreement Maturing June 1, 2021 [Member] | London Interbank Offered Rate (LIBOR) [Member]
Long-Term Debt [Line Items]
Spread over variable rate	0.50%
Term Loan Credit Agreement Maturing June 1, 2021 [Member] | Federal Funds Effective Rate [Member]
Long-Term Debt [Line Items]
Spread over variable rate	0.50%
Term Loan Credit Agreement Maturing June 1, 2021 [Member] | One-Month London Interbank Offered Rate [Member]
Long-Term Debt [Line Items]
Spread over variable rate	1.00%
Minimum [Member]
Long-Term Debt [Line Items]
Loan term	10 years
Maximum [Member]
Long-Term Debt [Line Items]
Loan term	30 years
Secured Debt [Member]
Long-Term Debt [Line Items]
Aggregate principal amount	$ 9,019				8,221
Percentage of fair value of cost of property additions certified to the Deed of Trust collateral agent	85.00%
Available bond credits	$ 1,973
Future debt subject to property additions to the Deed of Trust	2,602
Secured Debt [Member] | 2.75% Senior Notes due May 15, 2030 [Member]
Long-Term Debt [Line Items]
Aggregate principal amount	400
Secured Debt [Member] | 3.70% Senior Notes Due May 15, 2050 [Member]
Long-Term Debt [Line Items]
Aggregate principal amount	400
Secured Debt [Member] | Term Loan Credit Agreement Maturing October 6, 2020 [Member]
Long-Term Debt [Line Items]
Repayments of long-term debt	460
Secured Debt [Member] | Note Purchase Agreements [Member]
Long-Term Debt [Line Items]
Repayments of long-term debt	2
Unsecured Debt [Member] | Term Loan Credit Agreement Maturing October 6, 2020 [Member]
Long-Term Debt [Line Items]
Term loan					$ 460
Unsecured Debt [Member] | Term Loan Credit Agreement Maturing June 1, 2021 [Member]
Long-Term Debt [Line Items]
Term loan	$ 450

Long-Term Debt (Schedule Of Lon

Long-Term Debt (Schedule Of Long-Term Debt) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Total long-term debt	$ 9,469	$ 8,681
Unamortized discount and debt issuance costs	(65)	(56)
Less amount due currently	(148)	(608)
Long-term debt, less amounts due currently	9,256	8,017
Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	9,019	8,221
5.75% Fixed Senior Notes Due September 30, 2020 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 126	$ 126
Interest percentage	5.75%	5.75%
Due date	Sep. 30, 2020
8.50% Senior Notes, Series C, due December 30, 2020 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 13	$ 14
Interest percentage	8.50%	8.50%
Due date	Dec. 30, 2020
4.10% Fixed Senior Notes Due June 1, 2022 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 400	$ 400
Interest percentage	4.10%	4.10%
Due date	Jun. 1, 2022
7.00% Fixed Debentures Due September 1, 2022 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 482	$ 482
Interest percentage	7.00%	7.00%
Due date	Sep. 1, 2022
2.75% Senior Notes due June 1, 2024 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 500	$ 500
Interest percentage	2.75%	2.75%
Due date	Jun. 1, 2024
2.95% Fixed Senior Notes Due April 1, 2025 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 350	$ 350
Interest percentage	2.95%	2.95%
Due date	Apr. 1, 2025
3.86% Senior Notes, Series A, due December 3, 2025 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 174	$ 174
Interest percentage	3.86%	3.86%
Due date	Dec. 3, 2025
3.86% Senior Notes, Series B, due January 14, 2026 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 38	$ 38
Interest percentage	3.86%	3.86%
Due date	Jan. 14, 2026
3.70% Fixed Senior Notes Due November 15, 2028 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 650	$ 650
Interest percentage	3.70%	3.70%
Due date	Nov. 15, 2028
5.75% Fixed Senior Notes Due March 15, 2029 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 318	$ 318
Interest percentage	5.75%	5.75%
Due date	Mar. 15, 2029
7.25% Senior Notes, Series B, due December 30, 2029 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 36	$ 36
Interest percentage	7.25%	7.25%
Due date	Dec. 30, 2029
2.75% Senior Notes due May 15, 2030 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 400
Interest percentage	2.75%	2.75%
Due date	May 15, 2030
6.47% Senior Notes, Series A, due September 30, 2030 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 82	$ 83
Interest percentage	6.47%	6.47%
Due date	Sep. 30, 2030
7.00% Fixed Senior Notes Due May 1, 2032 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 500	$ 500
Interest percentage	7.00%	7.00%
Due date	May 1, 2032
7.25% Fixed Senior Notes Due January 15, 2033 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 350	$ 350
Interest percentage	7.25%	7.25%
Due date	Jan. 15, 2033
7.50% Fixed Senior Notes Due September 1, 2038 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 300	$ 300
Interest percentage	7.50%	7.50%
Due date	Sep. 1, 2038
5.25% Fixed Senior Notes Due September 30, 2040 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 475	$ 475
Interest percentage	5.25%	5.25%
Due date	Sep. 30, 2040
4.55% Fixed Senior Notes Due December 1, 2041 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 400	$ 400
Interest percentage	4.55%	4.55%
Due date	Dec. 1, 2041
5.30% Fixed Senior Notes Due June 1, 2042 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 500	$ 500
Interest percentage	5.30%	5.30%
Due date	Jun. 1, 2042
3.75% Fixed Senior Notes Due April 1, 2045 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 550	$ 550
Interest percentage	3.75%	3.75%
Due date	Apr. 1, 2045
3.80% Fixed Senior Notes Due September 30, 2047 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 325	$ 325
Interest percentage	3.80%	3.80%
Due date	Sep. 30, 2047
4.10% Fixed Senior Notes Due November 15, 2048 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 450	$ 450
Interest percentage	4.10%	4.10%
Due date	Nov. 15, 2048
3.80% Senior Notes, Due June 1, 2049 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 500	$ 500
Interest percentage	3.80%	3.80%
Due date	Jun. 1, 2049
3.10% Senior Notes, Due September 15, 2049 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 700	$ 700
Interest percentage	3.10%	3.10%
Due date	Sep. 15, 2049
3.70% Senior Notes Due May 15, 2050 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Secured long-term debt	$ 400
Interest percentage	3.70%	3.70%
Due date	May 15, 2050
Term Loan Credit Agreement Maturing October 6, 2020 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Term loan		$ 460
Due date	Oct. 6, 2020
Term Loan Credit Agreement Maturing June 1, 2021 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Term loan	$ 450
Due date	Jun. 1, 2021

Long-Term Debt (Schedule Of L_2

Long-Term Debt (Schedule Of Long-Term Debt Maturity) (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Long-Term Debt [Abstract]
2020 (excluding first three months of 2020)	$ 148
2021	459
2022	891
2023	10
2024	510
Thereafter	7,451
Unamortized discount and debt issuance costs	(65)	$ (56)
Total	$ 9,404

Commitments And Contingencies_2

Commitments And Contingencies (Narrative) (Details) - USD ($) $ in Millions	1 Months Ended
	Feb. 29, 2020	Dec. 31, 2019
Commitments And Contingencies [Abstract]
Lease term		15 years
Increase in lease obligation	$ 24

Commitments And Contingencies_3

Commitments And Contingencies (Schedule Of Operating Lease Maturity) (Details) $ in Millions	Mar. 31, 2020USD ($)
Commitments And Contingencies [Abstract]
2020 (remaining nine months)	$ 23
2021	28
2022	24
2023	18
2024	12
Thereafter	28
Total undiscounted lease payments	133
Less imputed interest	(12)
Total future minimum lease payments	$ 121

Membership Interests (Narrative

Membership Interests (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Apr. 29, 2020
Subsequent Event [Line Items]
Cash available for distribution	$ 301
Regulatory capitalization ratio, debt	57.50%
Regulatory capitalization ratio, equity	42.50%
Current regulatory capitalization ratio, debt	56.50%
Current regulatory capitalization ratio, equity	43.50%
Members contribution	$ 87	$ 70
Subsequent Event [Member]
Subsequent Event [Line Items]
Cash available for distribution			$ 91

Membership Interests (Schedule

Membership Interests (Schedule Of Cash Capital Contributions) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Membership Interests [Abstract]
Members contribution	$ 87	$ 70

Membership Interests (Schedul_2

Membership Interests (Schedule Of Distributions Paid) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Membership Interests [Abstract]
Amount	$ 91	$ 71

Membership Interests (Schedul_3

Membership Interests (Schedule Of Changes To Membership Interests) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Balance	$ 10,799
Net income	131	$ 116
Distributions	(91)	(71)
Capital contributions	87	70
Net effects of cash flow hedges	(23)	(4)
Defined benefit pension plans	1	1
Balance	10,904
Capital Accounts [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Balance	10,938	8,624
Net income	131	116
Distributions	(91)	(71)
Capital contributions	87	70
Net effects of cash flow hedges		4
Defined benefit pension plans
Balance	11,065	8,743
Accumulated Other Comprehensive Income (Loss) [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Balance	(139)	(164)
Net income
Distributions
Capital contributions
Net effects of cash flow hedges	(23)	(4)
Defined benefit pension plans	1	1
Balance	(161)	(167)
Membership Interests [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Balance	10,799	8,460
Net income	131	116
Distributions	(91)	(71)
Capital contributions	87	70
Net effects of cash flow hedges	(23)
Defined benefit pension plans	1	1
Balance	$ 10,904	$ 8,576

Membership Interests (Schedul_4

Membership Interests (Schedule Of Changes To Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	$ (139)
Balance at end of period	(161)
Tax benefit cash flow hedges	6
Cash Flow Hedges - Interest Rate Swap [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(18)	$ (16)
Defined benefit pension plans
Cash flow hedges — net decrease in fair value of derivatives (net of tax benefit of $6)	(23)
Amounts reclassified from accumulated other comprehensive income (loss) to capital account (Note 1)		4
Balance at end of period	(41)	(20)
Defined Benefit Pension and OPEB Plans [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(121)	(148)
Defined benefit pension plans	1	1
Cash flow hedges — net decrease in fair value of derivatives (net of tax benefit of $6)
Amounts reclassified from accumulated other comprehensive income (loss) to capital account (Note 1)
Balance at end of period	(120)	(147)
Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(139)	(164)
Defined benefit pension plans	1	1
Cash flow hedges — net decrease in fair value of derivatives (net of tax benefit of $6)	(23)
Amounts reclassified from accumulated other comprehensive income (loss) to capital account (Note 1)		4
Balance at end of period	$ (161)	$ (167)

Pension And OPEB Plans (Narrati

Pension And OPEB Plans (Narrative) (Details) $ in Millions	3 Months Ended
	Mar. 31, 2020USD ($)item
Defined Benefit Plan Disclosure [Line Items]
Number of defined pension plans in which the Company participates | item	2
Percentage of plan attributed to regulated business	100.00%
Oncor Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	3.12%
Expected return on plan assets	4.94%
Vistra Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	3.26%
Expected return on plan assets	4.89%
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Cash contributions	$ 13
Additional cash contributions	164
Additional cash contributions, next five years	$ 571
OPEB Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	3.29%
Expected return on plan assets	5.90%
Cash contributions	$ 10
Additional cash contributions	25
Additional cash contributions, next five years	$ 176

Pension And OPEB Plans (Schedul

Pension And OPEB Plans (Schedule Of Pension And OPEB Plan Costs) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Defined Benefit Plan Disclosure [Line Items]
Net costs	$ 23	$ 26
Less amounts deferred principally as property or a regulatory asset	(4)	(7)
Net amounts recognized as operation and maintenance expense or other deductions	19	19
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	8	7
Interest cost	25	32
Expected return on assets	(27)	(30)
Amortization of net loss	12	7
Net costs	18	16
OPEB Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	1	2
Interest cost	8	11
Expected return on assets	(2)	(2)
Amortization of prior service cost	(5)	(5)
Amortization of net loss	3	4
Net costs	$ 5	$ 10

Related-Party Transactions (Nar

Related-Party Transactions (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Related Party Transaction [Line Items]
Revenue	$ 1,072	$ 1,016
InfraREIT [Member]
Related Party Transaction [Line Items]
Revenue	3
Cash payments to vendors	$ 1

Related-Party Transactions (Sch

Related-Party Transactions (Schedule Of Trade Accounts And Other Receivables From Related Parties) (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Related Party Transaction [Line Items]
Texas margin taxes payable	$ 32	$ 22
Net payable (receivable)	32	19
Texas [Member]
Related Party Transaction [Line Items]
Texas margin taxes payable	28	22
Federal [Member]
Related Party Transaction [Line Items]
Federal income taxes payable (receivable)	4	(3)
Sempra Texas Holdings [Member]
Related Party Transaction [Line Items]
Net payable (receivable)	31	20
Sempra Texas Holdings [Member] | Texas [Member]
Related Party Transaction [Line Items]
Texas margin taxes payable	28	22
Sempra Texas Holdings [Member] | Federal [Member]
Related Party Transaction [Line Items]
Federal income taxes payable (receivable)	3	(2)
Texas Transmission and Investment LLC [Member]
Related Party Transaction [Line Items]
Net payable (receivable)	1	(1)
Texas Transmission and Investment LLC [Member] | Federal [Member]
Related Party Transaction [Line Items]
Federal income taxes payable (receivable)	$ 1	$ (1)

Supplementary Financial Infor_3

Supplementary Financial Information (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Supplemental Financial Information [Line Items]
Aggregate amortization expenses	$ 15
Goodwill	$ 4,740	$ 4,740
Trade Accounts Receivable [Member] | Nonaffiliated REP [Member]
Supplemental Financial Information [Line Items]
Concentration risk percentage	15.00%
Trade Accounts Receivable [Member] | Second Nonaffiliated REP [Member]
Supplemental Financial Information [Line Items]
Concentration risk percentage	11.00%

Supplementary Financial Infor_4

Supplementary Financial Information (Schedule Of Other Deductions And (Income)) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Supplementary Financial Information [Abstract]
Professional fees	$ 1	$ 3
Recoverable pension and OPEB - non-service	14	14
AFUDC equity income	(5)
Other, including interest income	3
Total other deductions and (income) - net	$ 13	$ 17

Supplementary Financial Infor_5

Supplementary Financial Information (Schedule Of Interest Expense And Related Charges) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Supplementary Financial Information [Abstract]
Interest	$ 101	$ 88
Amortization of debt issuance costs and discounts	3	1
Less allowance for funds used during construction – capitalized interest portion	(3)	(3)
Total interest expense and related charges	$ 101	$ 86

Supplementary Financial Infor_6

Supplementary Financial Information (Schedule Of Trade Accounts And Other Receivables) (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Supplementary Financial Information [Abstract]
Gross trade accounts and other receivables	$ 662	$ 666
Allowance for uncollectible accounts	(6)	(5)
Trade accounts receivable - net	$ 656	$ 661

Supplementary Financial Infor_7

Supplementary Financial Information (Summary of Investments And Other Property) (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Supplementary Financial Information [Abstract]
Assets related to employee benefit plans	$ 112	$ 119
Land	12	12
Other	2	2
Total investments and other property	$ 126	$ 133

Supplementary Financial Infor_8

Supplementary Financial Information (Schedule Of Property, Plant And Equipment) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Property Plant and Equipment [Line Items]
Total assets in service	$ 27,065	$ 26,749
Less accumulated depreciation	8,102	7,986
Net of accumulated depreciation	18,963	18,763
Construction work in progress	832	585
Held for future use	21	22
Property, plant and equipment - net	19,816	19,370
Distribution [Member]
Property Plant and Equipment [Line Items]
Total assets in service	$ 14,211	14,007
Composite depreciation rate	2.80%
Avg. life	35 years 10 months 24 days
Transmission [Member]
Property Plant and Equipment [Line Items]
Total assets in service	$ 11,201	11,094
Composite depreciation rate	2.90%
Avg. life	35 years
Other Assets [Member]
Property Plant and Equipment [Line Items]
Total assets in service	$ 1,653	$ 1,648
Composite depreciation rate	6.90%
Avg. life	14 years 7 months 6 days

Supplementary Financial Infor_9

Supplementary Financial Information (Schedule Of Intangible Assets) (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 1,513	$ 1,508
Accumulated Amortization	552	537
Net	961	971
Land Easements [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	576	575
Accumulated Amortization	108	107
Net	468	468
Capitalized Software [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	937	933
Accumulated Amortization	444	430
Net	$ 493	$ 503

Supplementary Financial Info_10

Supplementary Financial Information (Schedule Of Estimated Aggregate Amortization Expenses) (Details) $ in Millions	Mar. 31, 2020USD ($)
Supplementary Financial Information [Abstract]
2020	$ 61
2021	61
2022	61
2023	61
2024	$ 60

Supplementary Financial Info_11

Supplementary Financial Information (Schedule Of Employee Benefit Obligations And Other) (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Supplementary Financial Information [Abstract]
Retirement plans and other employee benefits	$ 1,810	$ 1,834
Operating lease liabilities	94	66
Investment tax credits	6	6
Other	88	74
Total employee benefit, operating lease and other obligations	$ 1,998	$ 1,980

Supplementary Financial Info_12

Supplementary Financial Information (Schedule Of Supplemental Cash Flow Information) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Supplementary Financial Information [Abstract]
Interest	$ 90	$ 56
Less capitalized interest	(3)	(3)
Interest payments (net of amounts capitalized)	87	53
Noncash increase in operating lease obligations for ROU assets	37	88
Noncash construction expenditures	$ 221	$ 168

Infrareit Acquisition (Narrativ

Infrareit Acquisition (Narrative) (Details) $ in Millions	May 16, 2019USD ($)	May 15, 2019MW	May 15, 2019kW	May 15, 2019property	May 15, 2019mi	Mar. 31, 2020USD ($)mikW
Business Acquisition [Line Items]
Repayment of debt						$ 462
InfraREIT [Member]
Business Acquisition [Line Items]
Repayment of debt	$ 602
Outstanding debt acquired	$ 351
Miles of assets transferred | mi					340	1,575
Number of assets transferred in circuit miles | mi						1,235
Power of number of transmission lines transferred		3,900	138			345
Number Of Operational Generation Facilities | property				20
Number Of Transmission Stations And Substations | property				50

Infrareit Acquisition (Total Pu

Infrareit Acquisition (Total Purchase Price Paid) (Details) - InfraREIT [Member] $ in Millions	3 Months Ended
	Mar. 31, 2020USD ($)
Purchase of outstanding InfraREIT shares and units	$ 1,275
Certain transaction costs of InfraREIT paid by Oncor	49
Total purchase price paid	1,324
Management termination fee	$ 40

Infrareit Acquisition (Pro Form

Infrareit Acquisition (Pro Forma Information) (Details) $ in Millions	3 Months Ended
	Mar. 31, 2020USD ($)
InfraREIT [Member]
Oncor Consolidated Pro Forma Revenues	$ 1,072